Investigate

Skill ialameh/sift-coder/skills/coding/investigate

Use when the user wants to understand a bug, behaviour, performance issue, or codebase area without making changes yet. READ-ONLY mode. Produces an evidence ledger and a hypothesis tree.From its SKILL.md

Install

npx -y skills add ialameh/sift-coder --skill investigate

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

One thing to look at

2 stars2 stars. Stars are a popularity signal and not a quality one, but at this level it is likely that nobody has read this closely except its author, and you would be relying on your own review.

SKILL.md

2.4 KB, as published. Nobody here has run it

investigate

Read-only diagnosis. Hypothesis-driven. Evidence-cited. Produces a written report — does NOT touch the code.

Method

Question. State the question in one line. Without a precise question, you'll wander.
Memory pass. Has this been investigated before? If so, surface that report and ask whether to re-run or update.
Hypothesis tree. List 3-5 hypotheses, ordered by likelihood. Each gets:
- Statement
- Evidence-needed-to-confirm
- Evidence-needed-to-rule-out
Evidence collection. For each hypothesis, gather evidence in order. Stop when one is confirmed or all are ruled out.
Report. Findings + remaining unknowns + recommended next action.

Output shape

Question:   <one line>
Method:     <brief — what was checked>

Hypotheses:
  H1 [confirmed|ruled-out|inconclusive] — <statement>
     Evidence: <bullets, file:line citations>
  H2 [...] — ...
  H3 [...] — ...

Conclusion: <one paragraph>
Next:       <recommended action, OR another investigation needed>
Captured:   <summary written to memory>

Rules

Read-only. No Edit, no Write. If you find yourself wanting to change code, stop and surface the recommendation — don't do it.
Every hypothesis claim cites evidence (file:line, log line, command output).
Inconclusive is a valid result. Say so.
No "could be" or "might be" without follow-up. Either confirm or rule out, or mark as needs-more-data.

Anti-patterns

Investigation that drifts into a fix (separate workflows)
Hypothesis-free wandering ("let me just look around")
"I think" without "because <evidence>"
One hypothesis tested → declared root cause without ruling out others

When NOT to use

You already know the cause and just need to fix — /siftcoder:fix
You need to add a feature — /siftcoder:add-feature
You want a generated story-shape explanation — /siftcoder:narrator

Subagent dispatch

investigator agent (read-only, hypothesis-tracking)
Explore for codebase mapping
archaeologist skill if the question is "why does this exist"

Memory capture

The report itself is captured as a summary with provenance edges to the files and symbols referenced. Future "did we investigate X" queries return this.