Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add existential-birds/beagle --skill python-code-reviewgit clone --depth 1 https://github.com/existential-birds/beagleWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/existential-birds/beagle/python-code-review)<a href="https://agentmods.dev/skills/existential-birds/beagle/python-code-review"><img src="https://agentmods.dev/badge/skills/existential-birds/beagle/python-code-review/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/existential-birds/beagle/python-code-review"><img src="https://agentmods.dev/badge/skills/existential-birds/beagle/python-code-review.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00041 | $0.01067 |
| Opus 5.5 | $0.00016 | $0.00427 |
| Sonnet 5.5 | $0.00008 | $0.00213 |
| Haiku 4.5 | $0.00004 | $0.00107 |
Grade A, and why
python-code-review scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Python Code Review
Quick Reference
| Issue Type | Reference |
|---|---|
| Indentation, line length, whitespace, naming | references/pep8-style.md |
| Missing/wrong type hints, Any usage | references/type-safety.md |
| Blocking calls in async, missing await | references/async-patterns.md |
| Bare except, missing context, logging | references/error-handling.md |
| Mutable defaults, print statements | references/common-mistakes.md |
Review Checklist
PEP8 Style
- 4-space indentation (no tabs)
- Line length ≤79 characters (≤72 for docstrings/comments)
- Two blank lines around top-level definitions, one within classes
- Imports grouped: stdlib → third-party → local (blank line between groups)
- No whitespace inside brackets or before colons/commas
- Naming:
snake_casefor functions/variables,CamelCasefor classes,UPPER_CASEfor constants - Inline comments separated by at least two spaces
Type Safety
- Type hints on all function parameters and return types
- No
Anyunless necessary (with comment explaining why) - Proper
T | Nonesyntax (Python 3.10+)
Async Patterns
- No blocking calls (
time.sleep,requests) in async functions - Proper
awaiton all coroutines
Error Handling
- No bare
except:clauses - Specific exception types with context
-
raise ... fromto preserve stack traces
Common Mistakes
- No mutable default arguments
- Using
loggernotprint()for output - f-strings preferred over
.format()or%
Valid Patterns (Do NOT Flag)
These patterns are intentional and correct - do not report as issues:
- Type annotation vs type assertion - Annotations declare types but are not runtime assertions; don't confuse with missing validation
- Using
Anywhen interacting with untyped libraries - Required when external libraries lack type stubs - Empty
__init__.pyfiles - Valid for package structure, no code required noqacomments - Valid when linter rule doesn't apply to specific case- Using
cast()after runtime type check - Correct pattern to inform type checker of narrowed type
What ships with it
5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago First seen · 96 lines · 41 tokens per session scan A 89840cbe9245
python-code-review is a skill published in the GitHub repository existential-birds/beagle (82 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 41 tokens to every session and 1,067 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-16.
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best-practices
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