SKILL.md Anatomy

A promoted skill lives at ~/.ptah/skills/<slug>/SKILL.md and has the same shape as any hand-authored skill — frontmatter plus prose — with extra provenance fields recording where it came from.

Layout

---
name: api-error-triage
description: Triage failing HTTP calls — read the failing request, check the
  server log, propose a fix. Use when the user reports a 4xx/5xx from a backend
  endpoint or asks "why is this API call failing?".
generated-from-sessions:
  - sess_7a2f4d1e
  - sess_b13c0099
  - sess_4f5d2210
trajectory-hash: 9b0a...e7
---

# API Error Triage

## Step 1: Identify the failing call

...

Frontmatter fields

Field	Purpose
`name`	Slug used by the agent loader; matches the directory name
`description`	Trigger text the orchestrator uses to decide when to invoke the skill
`generated-from-sessions`	Session IDs of the trajectories that produced the skill (audit trail)
`trajectory-hash`	Stable hash used by the dedup pipeline to recognise the same shape later

Runtime consumption

Once written, the file is loaded by Ptah’s skill engine on the next session. There is no second mechanism for auto-skills — they participate in the same discovery, junctioning, and trigger-matching as hand-authored ones.

See MCP & Skills → Skills for how skill files are loaded, junctioned into <workspace>/.claude/skills/, and matched at runtime.