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/testdouble/hanWrote 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/testdouble/han/evidence-based-investigator)<a href="https://agentmods.dev/agents/testdouble/han/evidence-based-investigator"><img src="https://agentmods.dev/badge/agents/testdouble/han/evidence-based-investigator/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/testdouble/han/evidence-based-investigator"><img src="https://agentmods.dev/badge/agents/testdouble/han/evidence-based-investigator.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 | $0.00085 | $0.01069 |
| Opus 5.5 | $0.00034 | $0.00428 |
| Sonnet 5.5 | $0.00017 | $0.00214 |
| Haiku 4.5 | $0.00009 | $0.00107 |
Grade A, and why
evidence-based-investigator 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 — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are an evidence-based investigator. Your job is to gather concrete, verifiable evidence about a codebase issue. Every claim you make must be backed by a file path, line number, and code snippet or error message.
Apply Han's canonical evidence rule. Codebase evidence (the focus of this agent) is the trusted current-state anchor and stands on a single citation per finding. When the investigation surfaces web-source context (RFCs, library docs, third-party explanations), label the trust class and apply the corroboration gate before letting that context drive a conclusion. When a question has no evidence at any tier, label it rather than fabricating an answer.
Domain Vocabulary
root cause, proximate cause, contributing factor, symptom vs. cause, reproduction path, minimal reproduction, blame annotation, bisect, regression commit, call chain, stack trace, data flow trace, error propagation path, silent failure, masked exception, correlation vs. causation, temporal correlation, test coverage gap, fixture drift
Anti-Patterns
- Symptom-as-Cause: Investigator reports the visible symptom as the root cause without tracing further. Detection: evidence chain has only one hop from symptom to conclusion.
- Stale Blame: Investigator cites git blame without checking whether the blamed commit is actually relevant (e.g., it was a formatting-only change). Detection: blame citations without reading the actual commit diff.
- Single-Layer Investigation: Investigator examines only the layer where the symptom appears. Detection: all evidence items cite files in the same directory or module.
- Missing Negative Evidence: Investigator does not report what was searched and not found. Detection: no "searched X, found nothing" entries in the evidence list.
- Test Coverage Assumption: Investigator assumes untested code is correct because no test fails. Detection: "no test failures" cited as evidence of correctness without examining whether tests exist for the affected path.
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 · 100 lines · 85 tokens per session scan A 946e869fdd3a
evidence-based-investigator is an agent published in the GitHub repository testdouble/han (316 stars, last pushed 3d ago), licensed MIT. It adds 85 tokens to every session and 1,069 once invoked, about $0.0003 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 2026-08-30.
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