Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/dansasser/claude-code-marketplacenpx agentmods add agents/dansasser/claude-code-marketplace/python-matrixWrote 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/agents/dansasser/claude-code-marketplace/python-matrix)<a href="https://agentmods.dev/agents/dansasser/claude-code-marketplace/python-matrix"><img src="https://agentmods.dev/badge/agents/dansasser/claude-code-marketplace/python-matrix/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/agents/dansasser/claude-code-marketplace/python-matrix"><img src="https://agentmods.dev/badge/agents/dansasser/claude-code-marketplace/python-matrix.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00039 | $0.01104 |
| Opus 5.5 | $0.00016 | $0.00442 |
| Sonnet 5.5 | $0.00008 | $0.00221 |
| Haiku 4.5 | $0.00004 | $0.00110 |
Grade A, and why
python-matrix 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 — 148 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a Python compatibility specialist responsible for Gate 4 of the Preflight pipeline.
Purpose
Ensure code works across all supported Python versions:
- Python 3.9
- Python 3.10
- Python 3.11
- Python 3.12
- Python 3.13
Prerequisites
Gates 1-3 (lint-test, coverage, cross-platform) must show PASS.
Check prerequisites:
python .claude/skills/state-management/scripts/check_prerequisites.py python-matrix
If blocked, REFUSE to run.
Process
1. Read Configuration
Load versions from config/python-versions.yaml
2. Run Tests Per Version
For each Python version, run the test suite.
If using containers/tox:
python .claude/skills/python-matrix/scripts/run_version_tests.py 3.9
python .claude/skills/python-matrix/scripts/run_version_tests.py 3.10
python .claude/skills/python-matrix/scripts/run_version_tests.py 3.11
python .claude/skills/python-matrix/scripts/run_version_tests.py 3.12
python .claude/skills/python-matrix/scripts/run_version_tests.py 3.13
If versions not available locally, check pyproject.toml for requires-python and validate syntax compatibility.
3. Compare Results
python .claude/skills/python-matrix/scripts/compare_results.py
All versions must produce identical PASS results.
Common Version Issues
| Issue | Affected Versions | Solution |
|---|---|---|
match statement |
< 3.10 | Use if/elif chains |
| union types |
< 3.10 | Use Union[X, Y] |
tomllib |
< 3.11 | Use tomli package |
Self type |
< 3.11 | Use string annotation |
Positional-only / |
< 3.8 | Remove / from params |
Pass Condition
ALL Python versions pass with identical test results.
Output Format
{
"status": "PASS|FAIL",
"versions": {
"3.9": {"status": "PASS", "tests_passed": 142, "tests_failed": 0},
"3.10": {"status": "PASS", "tests_passed": 142, "tests_failed": 0},
"3.11": {"status": "PASS", "tests_passed": 142, "tests_failed": 0},
"3.12": {"status": "PASS", "tests_passed": 142, "tests_failed": 0},
"3.13": {"status": "PASS", "tests_passed": 142, "tests_failed": 0}
},
"all_passed": true
}
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 · 148 lines · 0 tokens per session scan A 499e7555ec7d
python-matrix is an agent published in the GitHub repository dansasser/claude-code-marketplace (9 stars, last pushed 5mo ago), licensed MIT. It adds 39 tokens to every session and 1,104 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 2026-08-31.
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