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/assert-agent-story)<a href="https://agentmods.dev/rules/featurefactory-io/mimir/assert-agent-story"><img src="https://agentmods.dev/badge/rules/featurefactory-io/mimir/assert-agent-story/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/assert-agent-story"><img src="https://agentmods.dev/badge/rules/featurefactory-io/mimir/assert-agent-story.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 | $0.00546 | $0.00546 |
| Opus 5.5 | $0.00218 | $0.00218 |
| Sonnet 5.5 | $0.00109 | $0.00109 |
| Haiku 4.5 | $0.00055 | $0.00055 |
Grade A, and why
assert-agent-story 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 18d 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 — 31 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mimir metadata: slug do-assert-agent-story; always_apply: false (link to BPE-02 / MIN-04 / TFK-02 / DTA-19).
When a plan, iteration manifest, or SAO §17 row declares Agent proof scenarios (PRF-*, agent_proof_script[], or agent_proof_command), you MUST prove orchestration with pytest integration tests using CAP-004 ScriptedLLM and the shared trace helper — not by asserting chat prose, grepping logs/app.log alone, or "the agent loop exists" checklists.
Requirements
- For each PRF row mapped in SAO §17, a test asserts run trace beats (workflow, tools offered/called, domain effects, blackboard/plan state as applicable) via
tests/support/agent_story.py→assert_agent_story(...). - Cover happy and reject paths when the PRF is marked adverse or has a reject sketch (
test_*_agent_story_happy/test_*_agent_story_reject). - Use ordered LLM scripts from
tests/fixtures/llm_scripts/<prf-id>/injected through the agent factory — only CAP-004 ScriptedLLM may stand in for the LLM in integration tests. - Agent-proof tests ship in the same commit as the CAP/worker behavior they prove — never a deferred "agent testing pass".
- Never assert on raw secrets, tokens, or passwords in trace or log lines.
- Do not mock domain services, tools, or brokers in
@agent_prooftests — real DB and real tool registry per Test Trophy.
Relationship to log story
- Log story (
do-assert-log-story): proves logging beats at decision points (caplog). - Agent story: proves control-plane behavior (trace + domain) under scripted LLM turns.
- Both may apply to the same slice; both must green in the same commit when declared.
Anti-patterns
- Behavior test green while PRF trace absent or weakened to "agent completed"
FakeLLMthat returns[]on exhaustion instead of raising (hides missing script turns)- Mocking ToolExecutor or domain services in
@agent_proofintegration tests - Skipping
checkpoint.agent_proof_commandwhen the manifest lists PRF proofs - Using live LLM in PR merge gate (belongs to lane 3/4 — see TFK-01 §6)
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.
- 18d ago First seen · 31 lines · 546 tokens per session scan A 51b0a843e106
assert-agent-story is a cursor rule published in the GitHub repository FeatureFactory-io/mimir (16 stars, last pushed 17d ago), licensed Apache-2.0. It adds 546 tokens to every session, about $0.0022 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 2026-09-29.
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