diff --git a/.fix-pylint-output-for-gitlab-ci.py b/.fix-pylint-output-for-gitlab-ci.py
new file mode 100755
index 0000000..5de8f06
--- /dev/null
+++ b/.fix-pylint-output-for-gitlab-ci.py
@@ -0,0 +1,10 @@
+import re
+import sys
+
+def fix_output(matchobj):
+    return f'{matchobj.group(1)}{float(matchobj.group(2)) * 10}/{int(matchobj.group(3)) * 10}'
+
+pattern = re.compile(r'(Your code has been rated at )([0-9.]+)/(10)')
+for line in sys.stdin:
+    line.rstrip()
+    print(re.sub(pattern, fix_output, line), end='')
diff --git a/.gitignore b/.gitignore
index e695a0f..43f1f96 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,4 @@ __pycache__
 venv
 .env
 public
+*.swp
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 0ba1f5a..6cda68b 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,25 +1,52 @@
 image: python:3.11
 
 stages:
+  - install
   - test
   - deploy
 
-before_script:
-  - make install
+default:
+  cache: &global_cache
+    key: "$CI_COMMIT_SHA"
+    paths:
+      - venv/
+
+.pull-cache: &pull_cache
+  cache:
+    <<: *global_cache
+    policy: pull
+
+install:
+  stage: install
+  script:
+    - make venv
+  cache:
+    <<: *global_cache
+    policy: push
 
 pytest:
+  <<: *pull_cache
   stage: test
   script:
     - make tests
 
 djlint:
+  <<: *pull_cache
   stage: test
   script:
     - make djlint
 
-pages:
-  stage: deploy
+pylint:
+  <<: *pull_cache
+  stage: test
+  script:
+    - make pylint | python3 .fix-pylint-output-for-gitlab-ci.py
+  allow_failure: true
+  coverage: '/Your code has been rated at ([0-9.]+)\/100/'
 
+pages:
+  <<: *pull_cache
+  stage: deploy
   script:
     - pwd
     - ls
diff --git a/.pylintrc b/.pylintrc
new file mode 100644
index 0000000..041c69d
--- /dev/null
+++ b/.pylintrc
@@ -0,0 +1,645 @@
+[MAIN]
+
+# Analyse import fallback blocks. This can be used to support both Python 2 and
+# 3 compatible code, which means that the block might have code that exists
+# only in one or another interpreter, leading to false positives when analysed.
+analyse-fallback-blocks=no
+
+# Clear in-memory caches upon conclusion of linting. Useful if running pylint
+# in a server-like mode.
+clear-cache-post-run=no
+
+# Load and enable all available extensions. Use --list-extensions to see a list
+# all available extensions.
+#enable-all-extensions=
+
+# In error mode, messages with a category besides ERROR or FATAL are
+# suppressed, and no reports are done by default. Error mode is compatible with
+# disabling specific errors.
+#errors-only=
+
+# Always return a 0 (non-error) status code, even if lint errors are found.
+# This is primarily useful in continuous integration scripts.
+#exit-zero=
+
+# A comma-separated list of package or module names from where C extensions may
+# be loaded. Extensions are loading into the active Python interpreter and may
+# run arbitrary code.
+extension-pkg-allow-list=
+
+# A comma-separated list of package or module names from where C extensions may
+# be loaded. Extensions are loading into the active Python interpreter and may
+# run arbitrary code. (This is an alternative name to extension-pkg-allow-list
+# for backward compatibility.)
+extension-pkg-whitelist=
+
+# Return non-zero exit code if any of these messages/categories are detected,
+# even if score is above --fail-under value. Syntax same as enable. Messages
+# specified are enabled, while categories only check already-enabled messages.
+fail-on=
+
+# Specify a score threshold under which the program will exit with error.
+fail-under=10
+
+# Interpret the stdin as a python script, whose filename needs to be passed as
+# the module_or_package argument.
+#from-stdin=
+
+# Files or directories to be skipped. They should be base names, not paths.
+ignore=CVS
+
+# Add files or directories matching the regular expressions patterns to the
+# ignore-list. The regex matches against paths and can be in Posix or Windows
+# format. Because '\\' represents the directory delimiter on Windows systems,
+# it can't be used as an escape character.
+ignore-paths=
+
+# Files or directories matching the regular expression patterns are skipped.
+# The regex matches against base names, not paths. The default value ignores
+# Emacs file locks
+ignore-patterns=^\.#
+
+# List of module names for which member attributes should not be checked
+# (useful for modules/projects where namespaces are manipulated during runtime
+# and thus existing member attributes cannot be deduced by static analysis). It
+# supports qualified module names, as well as Unix pattern matching.
+ignored-modules=
+
+# Python code to execute, usually for sys.path manipulation such as
+# pygtk.require().
+#init-hook=
+
+# Use multiple processes to speed up Pylint. Specifying 0 will auto-detect the
+# number of processors available to use, and will cap the count on Windows to
+# avoid hangs.
+jobs=1
+
+# Control the amount of potential inferred values when inferring a single
+# object. This can help the performance when dealing with large functions or
+# complex, nested conditions.
+limit-inference-results=100
+
+# List of plugins (as comma separated values of python module names) to load,
+# usually to register additional checkers.
+load-plugins=
+
+# Pickle collected data for later comparisons.
+persistent=yes
+
+# Minimum Python version to use for version dependent checks. Will default to
+# the version used to run pylint.
+py-version=3.11
+
+# Discover python modules and packages in the file system subtree.
+recursive=no
+
+# Add paths to the list of the source roots. Supports globbing patterns. The
+# source root is an absolute path or a path relative to the current working
+# directory used to determine a package namespace for modules located under the
+# source root.
+source-roots=
+
+# When enabled, pylint would attempt to guess common misconfiguration and emit
+# user-friendly hints instead of false-positive error messages.
+suggestion-mode=yes
+
+# Allow loading of arbitrary C extensions. Extensions are imported into the
+# active Python interpreter and may run arbitrary code.
+unsafe-load-any-extension=no
+
+# In verbose mode, extra non-checker-related info will be displayed.
+#verbose=
+
+
+[BASIC]
+
+# Naming style matching correct argument names.
+argument-naming-style=snake_case
+
+# Regular expression matching correct argument names. Overrides argument-
+# naming-style. If left empty, argument names will be checked with the set
+# naming style.
+#argument-rgx=
+
+# Naming style matching correct attribute names.
+attr-naming-style=snake_case
+
+# Regular expression matching correct attribute names. Overrides attr-naming-
+# style. If left empty, attribute names will be checked with the set naming
+# style.
+#attr-rgx=
+
+# Bad variable names which should always be refused, separated by a comma.
+bad-names=foo,
+          bar,
+          baz,
+          toto,
+          tutu,
+          tata
+
+# Bad variable names regexes, separated by a comma. If names match any regex,
+# they will always be refused
+bad-names-rgxs=
+
+# Naming style matching correct class attribute names.
+class-attribute-naming-style=any
+
+# Regular expression matching correct class attribute names. Overrides class-
+# attribute-naming-style. If left empty, class attribute names will be checked
+# with the set naming style.
+#class-attribute-rgx=
+
+# Naming style matching correct class constant names.
+class-const-naming-style=UPPER_CASE
+
+# Regular expression matching correct class constant names. Overrides class-
+# const-naming-style. If left empty, class constant names will be checked with
+# the set naming style.
+#class-const-rgx=
+
+# Naming style matching correct class names.
+class-naming-style=PascalCase
+
+# Regular expression matching correct class names. Overrides class-naming-
+# style. If left empty, class names will be checked with the set naming style.
+#class-rgx=
+
+# Naming style matching correct constant names.
+const-naming-style=UPPER_CASE
+
+# Regular expression matching correct constant names. Overrides const-naming-
+# style. If left empty, constant names will be checked with the set naming
+# style.
+#const-rgx=
+
+# Minimum line length for functions/classes that require docstrings, shorter
+# ones are exempt.
+docstring-min-length=-1
+
+# Naming style matching correct function names.
+function-naming-style=snake_case
+
+# Regular expression matching correct function names. Overrides function-
+# naming-style. If left empty, function names will be checked with the set
+# naming style.
+#function-rgx=
+
+# Good variable names which should always be accepted, separated by a comma.
+good-names=i,
+           j,
+           k,
+           ex,
+           p,
+           db,
+           Run,
+           _
+
+# Good variable names regexes, separated by a comma. If names match any regex,
+# they will always be accepted
+good-names-rgxs=
+
+# Include a hint for the correct naming format with invalid-name.
+include-naming-hint=yes
+
+# Naming style matching correct inline iteration names.
+inlinevar-naming-style=any
+
+# Regular expression matching correct inline iteration names. Overrides
+# inlinevar-naming-style. If left empty, inline iteration names will be checked
+# with the set naming style.
+#inlinevar-rgx=
+
+# Naming style matching correct method names.
+method-naming-style=snake_case
+
+# Regular expression matching correct method names. Overrides method-naming-
+# style. If left empty, method names will be checked with the set naming style.
+#method-rgx=
+
+# Naming style matching correct module names.
+module-naming-style=snake_case
+
+# Regular expression matching correct module names. Overrides module-naming-
+# style. If left empty, module names will be checked with the set naming style.
+#module-rgx=
+
+# Colon-delimited sets of names that determine each other's naming style when
+# the name regexes allow several styles.
+name-group=
+
+# Regular expression which should only match function or class names that do
+# not require a docstring.
+no-docstring-rgx=^_
+
+# List of decorators that produce properties, such as abc.abstractproperty. Add
+# to this list to register other decorators that produce valid properties.
+# These decorators are taken in consideration only for invalid-name.
+property-classes=abc.abstractproperty
+
+# Regular expression matching correct type alias names. If left empty, type
+# alias names will be checked with the set naming style.
+#typealias-rgx=
+
+# Regular expression matching correct type variable names. If left empty, type
+# variable names will be checked with the set naming style.
+#typevar-rgx=
+
+# Naming style matching correct variable names.
+variable-naming-style=snake_case
+
+# Regular expression matching correct variable names. Overrides variable-
+# naming-style. If left empty, variable names will be checked with the set
+# naming style.
+#variable-rgx=
+
+
+[CLASSES]
+
+# Warn about protected attribute access inside special methods
+check-protected-access-in-special-methods=no
+
+# List of method names used to declare (i.e. assign) instance attributes.
+defining-attr-methods=__init__,
+                      __new__,
+                      setUp,
+                      asyncSetUp,
+                      __post_init__
+
+# List of member names, which should be excluded from the protected access
+# warning.
+exclude-protected=_asdict,_fields,_replace,_source,_make,os._exit
+
+# List of valid names for the first argument in a class method.
+valid-classmethod-first-arg=cls
+
+# List of valid names for the first argument in a metaclass class method.
+valid-metaclass-classmethod-first-arg=mcs
+
+
+[DESIGN]
+
+# List of regular expressions of class ancestor names to ignore when counting
+# public methods (see R0903)
+exclude-too-few-public-methods=
+
+# List of qualified class names to ignore when counting class parents (see
+# R0901)
+ignored-parents=
+
+# Maximum number of arguments for function / method.
+max-args=5
+
+# Maximum number of attributes for a class (see R0902).
+max-attributes=7
+
+# Maximum number of boolean expressions in an if statement (see R0916).
+max-bool-expr=5
+
+# Maximum number of branch for function / method body.
+max-branches=12
+
+# Maximum number of locals for function / method body.
+max-locals=15
+
+# Maximum number of parents for a class (see R0901).
+max-parents=7
+
+# Maximum number of public methods for a class (see R0904).
+max-public-methods=20
+
+# Maximum number of return / yield for function / method body.
+max-returns=6
+
+# Maximum number of statements in function / method body.
+max-statements=50
+
+# Minimum number of public methods for a class (see R0903).
+min-public-methods=2
+
+
+[EXCEPTIONS]
+
+# Exceptions that will emit a warning when caught.
+overgeneral-exceptions=builtins.BaseException,builtins.Exception
+
+
+[FORMAT]
+
+# Expected format of line ending, e.g. empty (any line ending), LF or CRLF.
+expected-line-ending-format=
+
+# Regexp for a line that is allowed to be longer than the limit.
+ignore-long-lines=^\s*(# )?<?https?://\S+>?$
+
+# Number of spaces of indent required inside a hanging or continued line.
+indent-after-paren=4
+
+# String used as indentation unit. This is usually "    " (4 spaces) or "\t" (1
+# tab).
+indent-string='    '
+
+# Maximum number of characters on a single line.
+max-line-length=100
+
+# Maximum number of lines in a module.
+max-module-lines=1000
+
+# Allow the body of a class to be on the same line as the declaration if body
+# contains single statement.
+single-line-class-stmt=no
+
+# Allow the body of an if to be on the same line as the test if there is no
+# else.
+single-line-if-stmt=no
+
+
+[IMPORTS]
+
+# List of modules that can be imported at any level, not just the top level
+# one.
+allow-any-import-level=
+
+# Allow explicit reexports by alias from a package __init__.
+allow-reexport-from-package=no
+
+# Allow wildcard imports from modules that define __all__.
+allow-wildcard-with-all=no
+
+# Deprecated modules which should not be used, separated by a comma.
+deprecated-modules=
+
+# Output a graph (.gv or any supported image format) of external dependencies
+# to the given file (report RP0402 must not be disabled).
+ext-import-graph=
+
+# Output a graph (.gv or any supported image format) of all (i.e. internal and
+# external) dependencies to the given file (report RP0402 must not be
+# disabled).
+import-graph=
+
+# Output a graph (.gv or any supported image format) of internal dependencies
+# to the given file (report RP0402 must not be disabled).
+int-import-graph=
+
+# Force import order to recognize a module as part of the standard
+# compatibility libraries.
+known-standard-library=
+
+# Force import order to recognize a module as part of a third party library.
+known-third-party=enchant
+
+# Couples of modules and preferred modules, separated by a comma.
+preferred-modules=
+
+
+[LOGGING]
+
+# The type of string formatting that logging methods do. `old` means using %
+# formatting, `new` is for `{}` formatting.
+logging-format-style=old
+
+# Logging modules to check that the string format arguments are in logging
+# function parameter format.
+logging-modules=logging
+
+
+[MESSAGES CONTROL]
+
+# Only show warnings with the listed confidence levels. Leave empty to show
+# all. Valid levels: HIGH, CONTROL_FLOW, INFERENCE, INFERENCE_FAILURE,
+# UNDEFINED.
+confidence=HIGH,
+           CONTROL_FLOW,
+           INFERENCE,
+           INFERENCE_FAILURE,
+           UNDEFINED
+
+# Disable the message, report, category or checker with the given id(s). You
+# can either give multiple identifiers separated by comma (,) or put this
+# option multiple times (only on the command line, not in the configuration
+# file where it should appear only once). You can also use "--disable=all" to
+# disable everything first and then re-enable specific checks. For example, if
+# you want to run only the similarities checker, you can use "--disable=all
+# --enable=similarities". If you want to run only the classes checker, but have
+# no Warning level messages displayed, use "--disable=all --enable=classes
+# --disable=W".
+disable=raw-checker-failed,
+        bad-inline-option,
+        locally-disabled,
+        file-ignored,
+        suppressed-message,
+        useless-suppression,
+        deprecated-pragma,
+        use-symbolic-message-instead,
+        use-implicit-booleaness-not-comparison-to-string,
+        use-implicit-booleaness-not-comparison-to-zero,
+        fixme,
+        too-few-public-methods,
+        unused-argument,
+        import-outside-toplevel,
+        no-self-argument,
+        singleton-comparison,
+        missing-module-docstring,
+        missing-class-docstring,
+        missing-function-docstring
+
+# Enable the message, report, category or checker with the given id(s). You can
+# either give multiple identifier separated by comma (,) or put this option
+# multiple time (only on the command line, not in the configuration file where
+# it should appear only once). See also the "--disable" option for examples.
+enable=
+
+
+[METHOD_ARGS]
+
+# List of qualified names (i.e., library.method) which require a timeout
+# parameter e.g. 'requests.api.get,requests.api.post'
+timeout-methods=requests.api.delete,requests.api.get,requests.api.head,requests.api.options,requests.api.patch,requests.api.post,requests.api.put,requests.api.request
+
+
+[MISCELLANEOUS]
+
+# List of note tags to take in consideration, separated by a comma.
+notes=FIXME,
+      XXX,
+      TODO
+
+# Regular expression of note tags to take in consideration.
+notes-rgx=
+
+
+[REFACTORING]
+
+# Maximum number of nested blocks for function / method body
+max-nested-blocks=5
+
+# Complete name of functions that never returns. When checking for
+# inconsistent-return-statements if a never returning function is called then
+# it will be considered as an explicit return statement and no message will be
+# printed.
+never-returning-functions=sys.exit,argparse.parse_error
+
+
+[REPORTS]
+
+# Python expression which should return a score less than or equal to 10. You
+# have access to the variables 'fatal', 'error', 'warning', 'refactor',
+# 'convention', and 'info' which contain the number of messages in each
+# category, as well as 'statement' which is the total number of statements
+# analyzed. This score is used by the global evaluation report (RP0004).
+evaluation=max(0, 0 if fatal else 10.0 - ((float(5 * error + warning + refactor + convention) / statement) * 10))
+
+# Template used to display messages. This is a python new-style format string
+# used to format the message information. See doc for all details.
+msg-template=
+
+# Set the output format. Available formats are: text, parseable, colorized,
+# json2 (improved json format), json (old json format) and msvs (visual
+# studio). You can also give a reporter class, e.g.
+# mypackage.mymodule.MyReporterClass.
+#output-format=
+
+# Tells whether to display a full report or only the messages.
+reports=no
+
+# Activate the evaluation score.
+score=yes
+
+
+[SIMILARITIES]
+
+# Comments are removed from the similarity computation
+ignore-comments=yes
+
+# Docstrings are removed from the similarity computation
+ignore-docstrings=yes
+
+# Imports are removed from the similarity computation
+ignore-imports=yes
+
+# Signatures are removed from the similarity computation
+ignore-signatures=yes
+
+# Minimum lines number of a similarity.
+min-similarity-lines=4
+
+
+[SPELLING]
+
+# Limits count of emitted suggestions for spelling mistakes.
+max-spelling-suggestions=4
+
+# Spelling dictionary name. No available dictionaries : You need to install
+# both the python package and the system dependency for enchant to work.
+spelling-dict=
+
+# List of comma separated words that should be considered directives if they
+# appear at the beginning of a comment and should not be checked.
+spelling-ignore-comment-directives=fmt: on,fmt: off,noqa:,noqa,nosec,isort:skip,mypy:
+
+# List of comma separated words that should not be checked.
+spelling-ignore-words=
+
+# A path to a file that contains the private dictionary; one word per line.
+spelling-private-dict-file=
+
+# Tells whether to store unknown words to the private dictionary (see the
+# --spelling-private-dict-file option) instead of raising a message.
+spelling-store-unknown-words=no
+
+
+[STRING]
+
+# This flag controls whether inconsistent-quotes generates a warning when the
+# character used as a quote delimiter is used inconsistently within a module.
+check-quote-consistency=no
+
+# This flag controls whether the implicit-str-concat should generate a warning
+# on implicit string concatenation in sequences defined over several lines.
+check-str-concat-over-line-jumps=no
+
+
+[TYPECHECK]
+
+# List of decorators that produce context managers, such as
+# contextlib.contextmanager. Add to this list to register other decorators that
+# produce valid context managers.
+contextmanager-decorators=contextlib.contextmanager
+
+# List of members which are set dynamically and missed by pylint inference
+# system, and so shouldn't trigger E1101 when accessed. Python regular
+# expressions are accepted.
+generated-members=
+
+# Tells whether to warn about missing members when the owner of the attribute
+# is inferred to be None.
+ignore-none=yes
+
+# This flag controls whether pylint should warn about no-member and similar
+# checks whenever an opaque object is returned when inferring. The inference
+# can return multiple potential results while evaluating a Python object, but
+# some branches might not be evaluated, which results in partial inference. In
+# that case, it might be useful to still emit no-member and other checks for
+# the rest of the inferred objects.
+ignore-on-opaque-inference=yes
+
+# List of symbolic message names to ignore for Mixin members.
+ignored-checks-for-mixins=no-member,
+                          not-async-context-manager,
+                          not-context-manager,
+                          attribute-defined-outside-init
+
+# List of class names for which member attributes should not be checked (useful
+# for classes with dynamically set attributes). This supports the use of
+# qualified names.
+ignored-classes=optparse.Values,thread._local,_thread._local,argparse.Namespace
+
+# Show a hint with possible names when a member name was not found. The aspect
+# of finding the hint is based on edit distance.
+missing-member-hint=yes
+
+# The minimum edit distance a name should have in order to be considered a
+# similar match for a missing member name.
+missing-member-hint-distance=1
+
+# The total number of similar names that should be taken in consideration when
+# showing a hint for a missing member.
+missing-member-max-choices=1
+
+# Regex pattern to define which classes are considered mixins.
+mixin-class-rgx=.*[Mm]ixin
+
+# List of decorators that change the signature of a decorated function.
+signature-mutators=
+
+
+[VARIABLES]
+
+# List of additional names supposed to be defined in builtins. Remember that
+# you should avoid defining new builtins when possible.
+additional-builtins=
+
+# Tells whether unused global variables should be treated as a violation.
+allow-global-unused-variables=yes
+
+# List of names allowed to shadow builtins
+allowed-redefined-builtins=
+
+# List of strings which can identify a callback function by name. A callback
+# name must start or end with one of those strings.
+callbacks=cb_,
+          _cb
+
+# A regular expression matching the name of dummy variables (i.e. expected to
+# not be used).
+dummy-variables-rgx=_+$|(_[a-zA-Z0-9_]*[a-zA-Z0-9]+?$)|dummy|^ignored_|^unused_
+
+# Argument names that match this expression will be ignored.
+ignored-argument-names=_.*|^ignored_|^unused_
+
+# Tells whether we should check for unused import in __init__ files.
+init-import=no
+
+# List of qualified module names which can have objects that can redefine
+# builtins.
+redefining-builtins-modules=six.moves,past.builtins,future.builtins,builtins,io
diff --git a/Makefile b/Makefile
index 47c5700..ae7b27d 100644
--- a/Makefile
+++ b/Makefile
@@ -5,18 +5,21 @@ ORANGE=\033[0;33m
 BLUE=\033[0;34m
 NC=\033[0m # No Color
 
+.PHONY: tests djlint pylint
+
 venv: ## Create the venv
 	python3 -m venv venv
-install: venv ## Install the project locally
 	venv/bin/pip install -e ".[dev,docs]"
 docs: cog ## Build the docs
 	venv/bin/sphinx-build docs public
 cog: ## Run cog, to integrate the CLI options to the docs.
 	venv/bin/cog -r docs/*.md
-tests: install ## Run the tests
+tests: venv ## Run the tests
 	venv/bin/pytest
-djlint: install
+djlint: venv
 	venv/bin/djlint --ignore=H030,H031 --lint argos/server/templates/*html
+pylint: venv
+	venv/bin/pylint argos
 
 help:
 	@python3 -c "$$PRINT_HELP_PYSCRIPT" < $(MAKEFILE_LIST)
diff --git a/argos/agent.py b/argos/agent.py
index e1dc0d4..fe3d222 100644
--- a/argos/agent.py
+++ b/argos/agent.py
@@ -1,10 +1,15 @@
+"""Argos agent
+
+Fetchs the tasks from the server, execute it and send the result to the server
+"""
 import asyncio
+import json
 import logging
 import socket
 from typing import List
 
 import httpx
-from tenacity import retry, wait_random
+from tenacity import retry, wait_random  # type: ignore
 
 from argos.checks import get_registered_check
 from argos.logging import logger
@@ -12,6 +17,7 @@ from argos.schemas import AgentResult, SerializableException, Task
 
 
 def log_failure(retry_state):
+    """Log failures, with a different log level depending on the number of attempts."""
     if retry_state.attempt_number < 1:
         loglevel = logging.INFO
     else:
@@ -33,21 +39,21 @@ class ArgosAgent:
         self.max_tasks = max_tasks
         self.wait_time = wait_time
         self.auth = auth
+        headers = {
+            "Authorization": f"Bearer {self.auth}",
+        }
+        self._http_client = httpx.AsyncClient(headers=headers)
 
         self.agent_id = socket.gethostname()
 
     @retry(after=log_failure, wait=wait_random(min=1, max=2))
     async def run(self):
-        logger.info(f"Running agent against {self.server}")
-        headers = {
-            "Authorization": f"Bearer {self.auth}",
-        }
-        self._http_client = httpx.AsyncClient(headers=headers)
+        logger.info("Running agent against %s", self.server)
         async with self._http_client:
             while "forever":
                 retry_now = await self._get_and_complete_tasks()
                 if not retry_now:
-                    logger.error(f"Waiting {self.wait_time} seconds before next retry")
+                    logger.error("Waiting %i seconds before next retry", self.wait_time)
                     await asyncio.sleep(self.wait_time)
 
     async def _complete_task(self, task: dict) -> dict:
@@ -59,10 +65,10 @@ class ArgosAgent:
             status = result.status
             context = result.context
 
-        except Exception as e:
+        except Exception as err:  # pylint: disable=broad-except
             status = "error"
-            context = SerializableException.from_exception(e)
-            msg = f"An exception occured when running {task}. {e.__class__.__name__} : {e}"
+            context = SerializableException.from_exception(err)
+            msg = f"An exception occured when running {task}. {err.__class__.__name__} : {err}"
             logger.error(msg)
         return AgentResult(task_id=task.id, status=status, context=context)
 
@@ -76,7 +82,7 @@ class ArgosAgent:
         if response.status_code == httpx.codes.OK:
             # XXX Maybe we want to group the tests by URL ? (to issue one request per URL)
             data = response.json()
-            logger.info(f"Received {len(data)} tasks from the server")
+            logger.info("Received %i tasks from the server", len(data))
 
             tasks = []
             for task in data:
@@ -86,13 +92,13 @@ class ArgosAgent:
                 results = await asyncio.gather(*tasks)
                 await self._post_results(results)
                 return True
-            else:
-                logger.error("Got no tasks from the server.")
-                return False
-        else:
-            logger.error(f"Failed to fetch tasks: {response.read()}")
+
+            logger.error("Got no tasks from the server.")
             return False
 
+        logger.error("Failed to fetch tasks: %s", response.read())
+        return False
+
     async def _post_results(self, results: List[AgentResult]):
         data = [r.model_dump() for r in results]
         response = await self._http_client.post(
@@ -100,7 +106,7 @@ class ArgosAgent:
         )
 
         if response.status_code == httpx.codes.CREATED:
-            logger.error(f"Successfully posted results {response.json()}")
+            logger.error("Successfully posted results %s", json.dumps(response.json()))
         else:
-            logger.error(f"Failed to post results: {response.read()}")
+            logger.error("Failed to post results: %s", response.read())
         return response
diff --git a/argos/checks/__init__.py b/argos/checks/__init__.py
index 8238d21..be78950 100644
--- a/argos/checks/__init__.py
+++ b/argos/checks/__init__.py
@@ -1,7 +1,11 @@
-from argos.checks.base import (
+from argos.checks.base import (  # NOQA
     BaseCheck,
     CheckNotFound,
     get_registered_check,
     get_registered_checks,
 )
-from argos.checks.checks import HTTPBodyContains, HTTPStatus, SSLCertificateExpiration
+from argos.checks.checks import (  # NOQA
+    HTTPBodyContains,
+    HTTPStatus,
+    SSLCertificateExpiration,
+)
diff --git a/argos/checks/base.py b/argos/checks/base.py
index 8781294..92f6b72 100644
--- a/argos/checks/base.py
+++ b/argos/checks/base.py
@@ -1,13 +1,17 @@
+"""Various base classes for checks"""
+
 from dataclasses import dataclass
-from typing import Type
+from typing import Type, Union
 
 import httpx
 from pydantic import BaseModel
 
-from argos.schemas import Task
+from argos.schemas.models import Task
 
 
 class Status:
+    """Possible statuses of the checks"""
+
     ON_CHECK = "on-check"
     SUCCESS = "success"
     FAILURE = "failure"
@@ -15,6 +19,8 @@ class Status:
 
 
 class Severity:
+    """Possible statuses of the checks’ results"""
+
     OK = "ok"
     WARNING = "warning"
     CRITICAL = "critical"
@@ -30,6 +36,7 @@ class Response:
 
     @classmethod
     def new(cls, status, **kwargs):
+        """Normalize results of checks."""
         if isinstance(status, bool):
             status = Status.SUCCESS if status else Status.FAILURE
 
@@ -63,9 +70,9 @@ class InvalidResponse(Exception):
 
 class BaseCheck:
     config: str
-    expected_cls: Type[BaseExpectedValue] = None
+    expected_cls: Union[None, Type[BaseExpectedValue]] = None
 
-    _registry = []
+    _registry = []  # type: ignore[var-annotated]
 
     def __init_subclass__(cls, **kwargs):
         super().__init_subclass__(**kwargs)
@@ -73,10 +80,12 @@ class BaseCheck:
 
     @classmethod
     def get_registered_checks(cls):
+        """Return existing checks"""
         return {c.config: c for c in cls._registry}
 
     @classmethod
     def get_registered_check(cls, name):
+        """Get a check from its name"""
         check = cls.get_registered_checks().get(name)
         if not check:
             raise CheckNotFound(name)
@@ -88,16 +97,20 @@ class BaseCheck:
 
     @property
     def expected(self):
-        return self.expected_cls(expected=self.task.expected).get_converted()
+        """Convert the task’s class to simpler class"""
+        if self.expected_cls is not None:
+            return self.expected_cls(expected=self.task.expected).get_converted()
+        return None
 
     def response(self, **kwargs):
+        """Ensure that the response has a status and return a Response"""
         if "status" not in kwargs:
             raise InvalidResponse(kwargs)
         status = kwargs.pop("status")
         return Response.new(status, **kwargs)
 
     @classmethod
-    async def finalize(self, config, result, **context):
+    async def finalize(cls, config, result, **context):
         """By default, the finalize considers that :
 
         - All FAILUREs should be reported as CRITICAL
@@ -109,9 +122,9 @@ class BaseCheck:
         """
         if result.status in (Status.SUCCESS, Status.ERROR):
             return result.status, Severity.OK
-        elif result.status == Status.FAILURE:
+        if result.status == Status.FAILURE:
             return result.status, Severity.CRITICAL
-        elif result.status == Status.ON_CHECK:
+        if result.status == Status.ON_CHECK:
             msg = (
                 "Status is 'on-check', but the Check class "
                 "didn't provide a finalize() method."
diff --git a/argos/checks/checks.py b/argos/checks/checks.py
index f8174dc..b23695c 100644
--- a/argos/checks/checks.py
+++ b/argos/checks/checks.py
@@ -1,3 +1,5 @@
+"""Define the available checks"""
+
 from datetime import datetime
 
 from argos.checks.base import (
@@ -61,18 +63,19 @@ class SSLCertificateExpiration(BaseCheck):
     async def finalize(cls, config, result, **context):
         if result.status != Status.ON_CHECK:
             return result.status, Severity.WARNING
-        elif "expires_in" in context:
+
+        if "expires_in" in context:
             thresholds = config.ssl.thresholds
             thresholds.sort()
             for days, severity in thresholds:
                 if context["expires_in"] < days:
                     return Status.FAILURE, severity
             return Status.SUCCESS, Severity.OK
-        else:
-            raise ValueError(
-                "The SSLCertificateExpiration check didn't provide an 'expires_in' "
-                "context variable."
-            )
+
+        raise ValueError(
+            "The SSLCertificateExpiration check didn't provide an 'expires_in' "
+            "context variable."
+        )
 
     @classmethod
     def get_description(cls, config):
diff --git a/argos/commands.py b/argos/commands.py
index e142203..793613c 100644
--- a/argos/commands.py
+++ b/argos/commands.py
@@ -36,7 +36,7 @@ def server():
     default="INFO",
     type=click.Choice(logging.LOG_LEVELS, case_sensitive=False),
 )
-def agent(server, auth, max_tasks, wait_time, log_level):
+def agent(server_url, auth, max_tasks, wait_time, log_level):
     """Get and run tasks to the provided server. Will wait for new tasks.
 
     Usage: argos agent https://argos.server "auth-token-here"
@@ -50,8 +50,8 @@ def agent(server, auth, max_tasks, wait_time, log_level):
     from argos.logging import logger
 
     logger.setLevel(log_level)
-    agent = ArgosAgent(server, auth, max_tasks, wait_time)
-    asyncio.run(agent.run())
+    agent_ = ArgosAgent(server_url, auth, max_tasks, wait_time)
+    asyncio.run(agent_.run())
 
 
 @server.command()
diff --git a/argos/logging.py b/argos/logging.py
index c441daf..74de43c 100644
--- a/argos/logging.py
+++ b/argos/logging.py
@@ -12,4 +12,4 @@ def set_log_level(log_level):
     if not isinstance(level, int):
         raise ValueError(f"Invalid log level: {log_level}")
     logger.setLevel(level=level)
-    logger.info("Log level set to {}".format(log_level))
+    logger.info("Log level set to %s", log_level)
diff --git a/argos/schemas/__init__.py b/argos/schemas/__init__.py
index ae8757c..e682aed 100644
--- a/argos/schemas/__init__.py
+++ b/argos/schemas/__init__.py
@@ -1,2 +1,2 @@
-from .config import *
-from .models import *
+from .config import *  # NOQA
+from .models import *  # NOQA
diff --git a/argos/schemas/config.py b/argos/schemas/config.py
index 486af14..df5bb3a 100644
--- a/argos/schemas/config.py
+++ b/argos/schemas/config.py
@@ -1,18 +1,21 @@
+"""Pydantic schemas for configuration
+
+For database models, see argos.server.models.
+"""
 from typing import Dict, List, Literal, Optional, Tuple
 
 from pydantic import BaseModel, ConfigDict, HttpUrl, field_validator
 from pydantic.functional_validators import BeforeValidator
 from typing_extensions import Annotated
 
+from argos.checks import get_registered_checks
 from argos.schemas.utils import string_to_duration
 
-# This file contains the pydantic schemas.
-# For the database models, check in argos.server.models.
-
 Severity = Literal["warning", "error", "critical"]
 
 
 def parse_threshold(value):
+    """Parse duration threshold for SSL certificate validity"""
     for duration_str, severity in value.items():
         days = string_to_duration(duration_str, "days")
         # Return here because it's one-item dicts.
@@ -36,17 +39,16 @@ class WebsiteCheck(BaseModel):
     def validate(cls, value):
         if isinstance(value, str):
             return {"expected": value}
-        elif isinstance(value, dict):
+        if isinstance(value, dict):
             return value
-        elif isinstance(value, list):
+        if isinstance(value, list):
             return {"expected": value}
-        else:
-            raise ValueError("Invalid type")
+
+        raise ValueError("Invalid type")
 
 
 def parse_checks(value):
-    # To avoid circular imports
-    from argos.checks import get_registered_checks
+    """Check that checks are valid (i.e. registered) checks"""
 
     available_names = get_registered_checks().keys()
 
@@ -76,26 +78,36 @@ class Website(BaseModel):
 
     @field_validator("frequency", mode="before")
     def parse_frequency(cls, value):
+        """Convert the configured frequency to hours"""
         if value:
             return string_to_duration(value, "hours")
 
+        return None
+
 
 class Service(BaseModel):
+    """List of agents’ token"""
+
     secrets: List[str]
 
 
 class Alert(BaseModel):
+    """List of way to handle alerts, by severity"""
+
     error: List[str]
     warning: List[str]
     alert: List[str]
 
 
 class General(BaseModel):
+    """Frequency for the checks and alerts"""
+
     frequency: int
     alerts: Alert
 
     @field_validator("frequency", mode="before")
     def parse_frequency(cls, value):
+        """Convert the configured frequency to minutes"""
         return string_to_duration(value, "minutes")
 
 
diff --git a/argos/schemas/models.py b/argos/schemas/models.py
index c3d0e82..8d3f0f9 100644
--- a/argos/schemas/models.py
+++ b/argos/schemas/models.py
@@ -1,3 +1,7 @@
+"""Pydantic schemas for data
+
+For database models, see argos.server.models.
+"""
 import traceback
 from datetime import datetime
 from typing import Literal
@@ -8,6 +12,7 @@ from pydantic import BaseModel, ConfigDict
 
 
 class Task(BaseModel):
+    """A task corresponds to a check to execute"""
     id: int
     url: str
     domain: str
@@ -19,27 +24,29 @@ class Task(BaseModel):
     model_config = ConfigDict(from_attributes=True)
 
     def __str__(self):
-        id = self.id
+        task_id = self.id
         url = self.url
         check = self.check
-        return f"Task ({id}): {url} - {check}"
+        return f"Task ({task_id}): {url} - {check}"
 
 
 class SerializableException(BaseModel):
+    """Task exception"""
     error_message: str
     error_type: str
     error_details: str
 
     @staticmethod
-    def from_exception(e: BaseException):
+    def from_exception(err: BaseException):
         return SerializableException(
-            error_message=str(e),
-            error_type=str(type(e).__name__),
+            error_message=str(err),
+            error_type=str(type(err).__name__),
             error_details=traceback.format_exc(),
         )
 
 
 class AgentResult(BaseModel):
+    """Task’s result sent by agent"""
     task_id: int
     # The on-check status means that the service needs to finish the check
     # and will then determine the severity.
diff --git a/argos/schemas/utils.py b/argos/schemas/utils.py
index b0bbaa8..517a441 100644
--- a/argos/schemas/utils.py
+++ b/argos/schemas/utils.py
@@ -1,7 +1,7 @@
-from typing import Literal
+from typing import Literal, Union
 
 
-def string_to_duration(value: str, target: Literal["days", "hours", "minutes"]):
+def string_to_duration(value: str, target: Literal["days", "hours", "minutes"]) -> Union[int,float]:
     """Convert a string to a number of hours, days or minutes"""
     num = int("".join(filter(str.isdigit, value)))
 
@@ -27,15 +27,14 @@ def string_to_duration(value: str, target: Literal["days", "hours", "minutes"]):
     elif "mo" in value:
         num = num * 60 * 24 * 30  # considers 30d in a month
     elif "y" in value:
-        num = num * 60 * 24 * 365
-    elif "m" in value:
-        num = num
-    else:
+        num = num * 60 * 24 * 365  # considers 365d in a year
+    elif "m" not in value:
         raise ValueError("Invalid duration value", value)
 
     if target == "hours":
-        num = num / 60
-    elif target == "days":
-        num = num / 60 / 24
+        return num / 60
+    if target == "days":
+        return num / 60 / 24
 
+    # target == "minutes"
     return num
diff --git a/argos/server/alerting.py b/argos/server/alerting.py
index d158833..5f5821a 100644
--- a/argos/server/alerting.py
+++ b/argos/server/alerting.py
@@ -1,6 +1,9 @@
 from argos.logging import logger
 
+# XXX Implement mail alerts https://framagit.org/framasoft/framaspace/argos/-/issues/15
+# XXX Implement gotify alerts https://framagit.org/framasoft/framaspace/argos/-/issues/16
 
 def handle_alert(config, result, task, severity):
+    """Dispatch alert through configured alert channels"""
     msg = f"task={task.id}, status={result.status}, {severity=}"
-    logger.error(f"Alerting stub: {msg}")
+    logger.error("Alerting stub: %s", msg)
diff --git a/argos/server/main.py b/argos/server/main.py
index 0375e73..ce3f534 100644
--- a/argos/server/main.py
+++ b/argos/server/main.py
@@ -12,86 +12,93 @@ from argos.server.settings import get_app_settings, read_yaml_config
 
 
 def get_application() -> FastAPI:
+    """Spawn Argos FastAPI server"""
     settings = get_app_settings()
-    app = FastAPI()
+    appli = FastAPI()
 
-    config = read_config(app, settings)
+    config = read_config(appli, settings)
 
     # Settings is the pydantic settings object
     # Config is the argos config object (built from yaml)
-    app.state.config = config
-    app.state.settings = settings
+    appli.state.config = config
+    appli.state.settings = settings
 
-    app.add_event_handler(
+    appli.add_event_handler(
         "startup",
-        create_start_app_handler(app),
+        create_start_app_handler(appli),
     )
-    app.add_event_handler(
+    appli.add_event_handler(
         "shutdown",
-        create_stop_app_handler(app),
+        create_stop_app_handler(appli),
     )
-    app.include_router(routes.api, prefix="/api")
-    app.include_router(routes.views)
-    app.mount("/static", StaticFiles(directory="argos/server/static"), name="static")
-    return app
+    appli.include_router(routes.api, prefix="/api")
+    appli.include_router(routes.views)
+    appli.mount("/static", StaticFiles(directory="argos/server/static"), name="static")
+    return appli
 
 
-def create_start_app_handler(app):
+def create_start_app_handler(appli):
+    """Warmup the server:
+    setup database connection and update the tasks in it before making it available
+    """
     async def read_config_and_populate_db():
-        setup_database(app)
+        setup_database(appli)
 
-        db = await connect_to_db(app)
-        await queries.update_from_config(db, app.state.config)
+        db = await connect_to_db(appli)
+        await queries.update_from_config(db, appli.state.config)
 
     return read_config_and_populate_db
 
 
-async def connect_to_db(app):
-    app.state.db = app.state.SessionLocal()
-    return app.state.db
+async def connect_to_db(appli):
+    appli.state.db = appli.state.SessionLocal()
+    return appli.state.db
 
 
-def create_stop_app_handler(app):
+def create_stop_app_handler(appli):
+    """Gracefully shutdown the server:
+    close database connection.
+    """
     async def stop_app():
-        app.state.db.close()
+        appli.state.db.close()
 
     return stop_app
 
 
-def read_config(app, settings):
+def read_config(appli, settings):
     try:
         config = read_yaml_config(settings.yaml_file)
-        app.state.config = config
+        appli.state.config = config
         return config
-    except ValidationError as e:
+    except ValidationError as err:
         logger.error("Errors where found while reading configuration:")
-        for error in e.errors():
-            logger.error(f"{error['loc']} is {error['type']}")
+        for error in err.errors():
+            logger.error("%s is %s", error['loc'], error['type'])
         sys.exit(1)
 
 
-def setup_database(app):
-    settings = app.state.settings
+def setup_database(appli):
+    settings = appli.state.settings
     # For sqlite, we need to add connect_args={"check_same_thread": False}
-    logger.debug(f"Using database URL {settings.database_url}")
+    logger.debug("Using database URL %s", settings.database_url)
     if settings.database_url.startswith("sqlite:////tmp"):
         logger.warning("Using sqlite in /tmp is not recommended for production")
-    
+
     extra_settings = {}
     if settings.db_pool_size:
         extra_settings.setdefault("pool_size", settings.db_pool_size)
 
     if settings.db_max_overflow:
         extra_settings.setdefault("max_overflow", settings.db_max_overflow)
-        
+
     engine = create_engine(
         settings.database_url,
         **extra_settings
     )
-    app.state.SessionLocal = sessionmaker(
+    appli.state.SessionLocal = sessionmaker(
         autocommit=False, autoflush=False, bind=engine
     )
-    app.state.engine = engine
+    appli.state.engine = engine
     models.Base.metadata.create_all(bind=engine)
 
 
diff --git a/argos/server/models.py b/argos/server/models.py
index a894ab6..53e3b28 100644
--- a/argos/server/models.py
+++ b/argos/server/models.py
@@ -1,3 +1,4 @@
+"""Database models"""
 from datetime import datetime, timedelta
 from typing import List, Literal
 
@@ -20,8 +21,8 @@ class Task(Base):
     """
     There is one task per check.
 
-    It contains all information needed to run the jobs on the workers.
-    Workers will return information in the result table.
+    It contains all information needed to run the jobs on the agents.
+    Agents will return information in the result table.
     """
 
     __tablename__ = "tasks"
@@ -50,6 +51,7 @@ class Task(Base):
         return get_registered_check(self.check)
 
     def set_times_and_deselect(self):
+        """Removes the lock on task and set the time for the next run"""
         self.selected_by = None
 
         now = datetime.now()
@@ -58,24 +60,34 @@ class Task(Base):
 
     @property
     def last_result(self):
+        """Get last result of the task"""
         if not self.results:
             return None
         return max(self.results, key=lambda r: r.id)
 
     @property
     def status(self):
+        """Get status of the task, i.e. the status of its last result"""
         if not self.last_result:
             return None
         return self.last_result.status
 
     @property
     def severity(self):
+        """Get severity of the task"""
         if not self.last_result:
             return None
         return self.last_result.severity
 
 
 class Result(Base):
+    """There is multiple results per tasks.
+
+    The results uses the informations returned by the agents.
+
+    The status is "Was the agent able to do the check?" while the severity
+    depends on the return value of the check.
+    """
     __tablename__ = "results"
     id: Mapped[int] = mapped_column(primary_key=True)
     task_id: Mapped[int] = mapped_column(ForeignKey("tasks.id"))
diff --git a/argos/server/queries.py b/argos/server/queries.py
index aa3b863..420fe3b 100644
--- a/argos/server/queries.py
+++ b/argos/server/queries.py
@@ -1,3 +1,4 @@
+"""Functions to ease SQL queries management"""
 from datetime import datetime, timedelta
 from urllib.parse import urljoin
 
@@ -29,8 +30,8 @@ async def list_tasks(db: Session, agent_id: str, limit: int = 100):
     return tasks
 
 
-async def get_task(db: Session, id: int) -> Task:
-    return db.get(Task, id)
+async def get_task(db: Session, task_id: int) -> Task:
+    return db.get(Task, task_id)
 
 
 async def create_result(db: Session, agent_result: schemas.AgentResult, agent_id: str):
@@ -60,6 +61,7 @@ async def count_results(db: Session):
 
 
 async def update_from_config(db: Session, config: schemas.Config):
+    """Update tasks from config file"""
     tasks = []
     unique_properties = []
     for website in config.websites:
@@ -84,8 +86,9 @@ async def update_from_config(db: Session, config: schemas.Config):
 
                     if frequency != existing_task.frequency:
                         existing_task.frequency = frequency
-                    msg = f"Skipping db task creation for {url=}, {check_key=}, {expected=}, {frequency=}."
-                    logger.debug(msg)
+                    logger.debug("Skipping db task creation for url=%s, " \
+                                 "check_key=%s, expected=%s, frequency=%s.",
+                                 url, check_key, expected, frequency)
 
                 else:
                     properties = (url, check_key, expected)
@@ -98,7 +101,7 @@ async def update_from_config(db: Session, config: schemas.Config):
                             expected=expected,
                             frequency=frequency,
                         )
-                        logger.debug(f"Adding a new task in the db: {task}")
+                        logger.debug("Adding a new task in the db: %s", task)
                         tasks.append(task)
 
     db.add_all(tasks)
@@ -106,16 +109,17 @@ async def update_from_config(db: Session, config: schemas.Config):
 
 
 async def get_severity_counts(db: Session) -> dict:
+    """Get the severities (ok, warning, critical…) and their count"""
     # Get the last result of each task
     subquery = (
-        db.query(Result.task_id, func.max(Result.id).label("max_result_id"))
+        db.query(Result.task_id, func.max(Result.id).label("max_result_id")) #  pylint: disable-msg=not-callable
         .group_by(Result.task_id)
         .subquery()
     )
 
     # Join this back to get full result rows, and group by status
     query = (
-        db.query(Result.severity, func.count(Result.id).label("count"))
+        db.query(Result.severity, func.count(Result.id).label("count")) #  pylint: disable-msg=not-callable
         .join(subquery, Result.id == subquery.columns.max_result_id)
         .group_by(Result.severity)
     )
@@ -141,7 +145,7 @@ async def remove_old_results(db: Session, max_results: int):
             .limit(max_results)
             .subquery()
         )
-        min_id = db.query(func.min(subquery.c.id)).scalar()
+        min_id = db.query(func.min(subquery.c.id)).scalar() #  pylint: disable-msg=not-callable
 
         # Delete all the results older than min_id
         if min_id:
@@ -156,6 +160,7 @@ async def remove_old_results(db: Session, max_results: int):
 
 
 async def release_old_locks(db: Session, max_lock_seconds: int):
+    """Remove outdated locks on tasks"""
     # Get all the jobs that have been selected_at for more than max_lock_time
     max_acceptable_time = datetime.now() - timedelta(seconds=max_lock_seconds)
     subquery = (
diff --git a/argos/server/routes/api.py b/argos/server/routes/api.py
index 18e7b9b..57001c6 100644
--- a/argos/server/routes/api.py
+++ b/argos/server/routes/api.py
@@ -1,4 +1,5 @@
-from typing import List
+"""Web interface for machines"""
+from typing import List, Union
 
 from fastapi import APIRouter, Depends, Request
 from sqlalchemy.orm import Session
@@ -17,8 +18,9 @@ async def read_tasks(
     request: Request,
     db: Session = Depends(get_db),
     limit: int = 10,
-    agent_id: str = None,
+    agent_id: Union[None,str] = None,
 ):
+    """Return a list of tasks to execute"""
     agent_id = agent_id or request.client.host
     tasks = await queries.list_tasks(db, agent_id=agent_id, limit=limit)
     return tasks
@@ -30,7 +32,7 @@ async def create_results(
     results: List[AgentResult],
     db: Session = Depends(get_db),
     config: Config = Depends(get_config),
-    agent_id: str = None,
+    agent_id: Union[None,str] = None,
 ):
     """Get the results from the agents and store them locally.
 
@@ -47,7 +49,7 @@ async def create_results(
         # XXX Get all the tasks at once, to limit the queries on the db
         task = await queries.get_task(db, agent_result.task_id)
         if not task:
-            logger.error(f"Unable to find task {agent_result.task_id}")
+            logger.error("Unable to find task %i", agent_result.task_id)
         else:
             check = task.get_check()
             status, severity = await check.finalize(config, result, **result.context)
@@ -63,6 +65,7 @@ async def create_results(
 
 @route.get("/stats")
 async def get_stats(db: Session = Depends(get_db)):
+    """Get tasks statistics"""
     return {
         "upcoming_tasks_count": await queries.count_tasks(db, selected=False),
         "results_count": await queries.count_results(db),
diff --git a/argos/server/routes/dependencies.py b/argos/server/routes/dependencies.py
index 7c5eb61..e543eea 100644
--- a/argos/server/routes/dependencies.py
+++ b/argos/server/routes/dependencies.py
@@ -19,6 +19,7 @@ def get_config(request: Request):
 async def verify_token(
     request: Request, token: HTTPAuthorizationCredentials = Depends(auth_scheme)
 ):
+    """Verify agent token"""
     if token.credentials not in request.app.state.config.service.secrets:
         raise HTTPException(status_code=401, detail="Unauthorized")
     return token
diff --git a/argos/server/routes/views.py b/argos/server/routes/views.py
index 174f0c6..287168d 100644
--- a/argos/server/routes/views.py
+++ b/argos/server/routes/views.py
@@ -1,3 +1,4 @@
+"""Web interface for humans"""
 from collections import defaultdict
 from urllib.parse import urlparse
 
@@ -18,7 +19,7 @@ templates = Jinja2Templates(directory="argos/server/templates")
 
 @route.get("/")
 async def get_severity_counts(request: Request, db: Session = Depends(get_db)):
-    """Returns the number of results per severity"""
+    """Shows the number of results per severity"""
     counts_dict = await queries.get_severity_counts(db)
 
     agents = db.query(Result.agent_id).distinct().all()
@@ -35,6 +36,7 @@ async def get_severity_counts(request: Request, db: Session = Depends(get_db)):
 
 @route.get("/details")
 async def read_tasks(request: Request, db: Session = Depends(get_db)):
+    """Show all tasks and their current state"""
     tasks = db.query(Task).order_by(Task.domain).all()
 
     results = (
@@ -79,7 +81,8 @@ async def read_tasks(request: Request, db: Session = Depends(get_db)):
 async def get_domain_tasks(
     request: Request, domain: str, db: Session = Depends(get_db)
 ):
-    tasks = db.query(Task).filter(Task.domain.contains(domain)).all()
+    """Show all tasks attached to a domain"""
+    tasks = db.query(Task).filter(Task.domain.contains(domain)).all()  # type: ignore[attr-defined]
     return templates.TemplateResponse(
         "domain.html", {"request": request, "domain": domain, "tasks": tasks}
     )
@@ -87,6 +90,7 @@ async def get_domain_tasks(
 
 @route.get("/result/{result_id}")
 async def get_result(request: Request, result_id: int, db: Session = Depends(get_db)):
+    """Show the details of a result"""
     result = db.query(Result).get(result_id)
     return templates.TemplateResponse(
         "result.html", {"request": request, "result": result}
@@ -100,10 +104,11 @@ async def get_task_results(
     db: Session = Depends(get_db),
     config: Config = Depends(get_config),
 ):
+    """Show history of a task’s results"""
     results = (
         db.query(Result)
         .filter(Result.task_id == task_id)
-        .order_by(Result.submitted_at.desc())
+        .order_by(Result.submitted_at.desc())  # type: ignore[attr-defined]
         .all()
     )
     task = db.query(Task).get(task_id)
@@ -121,6 +126,7 @@ async def get_task_results(
 
 @route.get("/agents")
 async def get_agents(request: Request, db: Session = Depends(get_db)):
+    """Show argos agents and the last time the server saw them"""
     t1 = aliased(Result, name="t1")
     t2 = aliased(Result, name="t2")
 
diff --git a/argos/server/settings.py b/argos/server/settings.py
index 8116bb1..0465f77 100644
--- a/argos/server/settings.py
+++ b/argos/server/settings.py
@@ -1,7 +1,8 @@
+"""Pydantic schemas for server"""
 import os
 from functools import lru_cache
 from os import environ
-from typing import Optional
+from typing import Optional,Union
 
 import yaml
 from pydantic_settings import BaseSettings, SettingsConfigDict
@@ -20,14 +21,22 @@ class Settings(BaseSettings):
 
 
 class DevSettings(Settings):
+    """Settings for dev environment.
+
+    Uses config.yaml as config file.
+    Uses a SQLite database."""
     app_env: str = "dev"
-    database_url: str = "sqlite:////tmp/argos.db"
     yaml_file: str = "config.yaml"
     db_pool_size: Optional[int] = None
     db_max_overflow: Optional[int] = None
+    database_url: str = "sqlite:////tmp/argos.db"
 
 
 class TestSettings(Settings):
+    """Settings for test environment.
+
+    Uses tests/config.yaml as config file.
+    Uses a SQLite database."""
     app_env: str = "test"
     yaml_file: str = "tests/config.yaml"
     database_url: str = "sqlite:////tmp/test-argos.db"
@@ -36,6 +45,7 @@ class TestSettings(Settings):
 
 
 class ProdSettings(Settings):
+    """Settings for prod environment."""
     app_env: str = "prod"
     db_pool_size: Optional[int] = 10
     db_max_overflow: Optional[int] = 20
@@ -49,10 +59,13 @@ environments = {
 
 
 @lru_cache()
-def get_app_settings() -> Settings:
+def get_app_settings() -> Union[None,Settings]:
+    """Load settings depending on the environment"""
     app_env = environ.get("ARGOS_APP_ENV", "dev")
     settings = environments.get(app_env)
-    return settings()
+    if settings is not None:
+        return settings()
+    return None
 
 
 def read_yaml_config(filename):
@@ -66,5 +79,5 @@ def _load_yaml(filename):
         loader_class=yaml.FullLoader, base_dir=base_dir
     )
 
-    with open(filename, "r") as stream:
+    with open(filename, "r", encoding='utf-8') as stream:
         return yaml.load(stream, Loader=yaml.FullLoader)
diff --git a/config.yaml b/config.yaml
new file mode 100644
index 0000000..634628b
--- /dev/null
+++ b/config.yaml
@@ -0,0 +1,25 @@
+general:
+  frequency: "5m" # Run checks every minute.
+  alerts:
+    error:
+      - local
+    warning:
+      - local
+    alert:
+      - local
+service:
+  secrets:
+    - Shorts-Tribunal-Plentiful-Penknife-Lazily-Move0
+    # Secrets can be generated using `openssl rand -base64 32`.
+
+ssl:
+  thresholds:
+    - "15d": critical
+    - "25d": warning
+
+# It's also possible to define the checks in another file
+# with the include syntax:
+# 
+#   websites: !include websites.yaml
+#
+websites: !include websites.yaml
diff --git a/pyproject.toml b/pyproject.toml
index 7593da0..f4a47ff 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -42,7 +42,8 @@ dev = [
   "ipdb>=0.13,<0.14",
   "sphinx-autobuild",
   "ruff==0.1.5,<1",
-  "djlint>=1.34.0"
+  "djlint>=1.34.0",
+  "pylint>=3.0.2",
 ]
 postgres = [
   "psycopg2-binary>=2.9,<3",