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.
git clone --depth 1 https://github.com/FeatureFactory-io/mimirWrote 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/rules/featurefactory-io/mimir/do-docstring-format)<a href="https://agentmods.dev/rules/featurefactory-io/mimir/do-docstring-format"><img src="https://agentmods.dev/badge/rules/featurefactory-io/mimir/do-docstring-format/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/rules/featurefactory-io/mimir/do-docstring-format"><img src="https://agentmods.dev/badge/rules/featurefactory-io/mimir/do-docstring-format.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 | $0.00000 | $0.00297 |
| Opus 5.5 | $0.00000 | $0.00119 |
| Sonnet 5.5 | $0.00000 | $0.00059 |
| Haiku 4.5 | $0.00000 | $0.00030 |
Grade A, and why
do-docstring-format 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.
What it actually says
Docstring format (with examples)
Every public function/method needs a docstring in this shape:
def name(p: T) -> R:
"""
One-line summary.
:param p: what it is as Type. Example: concrete_value
:return: what you return as Type. Example: concrete_value
:raises SomeError: when
"""
Rules: summary line, blank line, then :param / :return / :raises with example values on every param and return (and raises where applicable). Types belong in the signature; docstring repeats them for humans.
Minimal good example
def get_workflow(workflow_id: str) -> dict:
"""
Load workflow by id.
:param workflow_id: id as str. Example: "a1b2c3d4-e5f6-7890-abcd-ef1234567890"
:return: workflow dict. Example: {"id": "a1b2c3d4", "name": "Build Feature"}
:raises ValueError: if id invalid
"""
Anti-patterns: no examples; vague "the name"; missing return example; docstring contradicts implementation (ask user which wins).
**Optional / *args / kwargs: document each; examples show typical values.
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 · 38 lines · 0 tokens per session scan A f9e1df83d510
do-docstring-format is a cursor rule published in the GitHub repository FeatureFactory-io/mimir (16 stars, last pushed 17d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 297 tokens. 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 2026-08-30.
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