make skill selection work outside Claude Code

[chiruu12]

Nothing in a skill description said what the skill is not for, so the confusable
pairs had nothing separating them at selection time. And the README told nine
platforms to type a Claude Code slash command.

What each skill is not for

All 15 descriptions now carry a "Not for X, use Y" line. Eight were missing one,
and they were the confusable ones: find-issue against find-real-issues,
explore-repo against learn-stack, contribute against write-tests and write-docs,
submit-pr against post-pr, prep-to-contribute against setup-dev-env.

This is not a Claude Code thing. Cursor, Cline and Windsurf decide whether a rule
fires by reading its description, so a description that does not rule itself out
means the wrong skill loads, or none does.

The router carries it too

Targets with a router (agents, gemini, copilot, zed) strip frontmatter from the
bodies in .oss-skills/, and the router only carried the first line of each
description. So the disambiguation was reaching 5 of 9 targets. write_router
now emits the "Not for" line under each summary. Router goes 3.4KB to 4.3KB.

README

The headline listed nine tools and then said "Run /oss-find-issue". Slash
commands exist on one of them. Also fixed: "executable Claude Code skills", the
Requirements table naming Claude Code as the runtime, and Troubleshooting only
knowing where the Claude install lands. Added an entry for "installed, but the
agent never uses them", which is the failure people will actually hit.

Test

One new CI step, checked failing on c594399 both ways: once for a description
with no "Not for" line, once for a router that drops it. 23 steps green locally.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[greptile-apps]

Greptile Summary

The PR adds explicit negative routing guidance to skill descriptions and propagates that guidance into generated router files. It also updates cross-platform usage and troubleshooting documentation.

• Adds “Not for” disambiguation to confusable skill descriptions.
• Includes disambiguation guidance in router-based installation targets.
• Updates README and platform documentation for non-Claude tools.
• Adds CI coverage for the presence and propagation of routing guidance.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
setup	Adds description extraction and emits each skill’s negative-selection guidance beneath its router entry.
.github/workflows/setup.yml	Adds CI validation that every skill supplies negative-selection guidance and every generated router entry carries it.
README.md	Reworks invocation, requirements, installation checks, and troubleshooting guidance for all supported tools.
CLAUDE.md	Documents the required placement and purpose of negative-selection guidance in skill descriptions.
docs/PLATFORMS.md	Updates the documented approximate size of generated router files.

_{Reviews (2): Last reviewed commit: "document the description disambiguation ..." | Re-trigger Greptile}

[greptile-apps]

Extraction includes trailing description text

skill_notfor returns everything from the first Not for occurrence through the end of the description, so placing later explanatory text after that sentence adds unrelated content to the generated router guidance; the new CI check still passes because it validates only the line prefix and count.