chore: document skill workflows, replace tessl with skill-check

[jamesc]

Summary

Documents the skill workflows in the README and replaces the unused tessl integration with skill-check for skill validation.

Key changes

• README: new Workflows section summarising how the skills compose — planning via ADR (/draft-adr → /review-adr → /plan-adr), the build loop (/pick-issue → /review-code → /done → /resolve-pr), parallel epic execution, refactoring, issue management, and utilities.
• CI: removed the tessl-lint, tessl-review, and tessl-publish jobs. Lint/review were silently no-ops (they only process skills with a tile.json, and none exist) and publishing isn't wanted. Added a skill-check lint step (--fail-on-warning, GitHub annotations) to the validate job.
• Setup: removed tessl install from scripts/setup-env.sh and the session-start hook (was running npm install -g tessl on every session start).
• skill-check.config.json: disables frontmatter.unknown_fields (Claude Code supports model/argument-hint beyond the agentskills.io spec). Security scan stays off — its backend (snyk-agent-scan) now requires a Snyk account token; deliberate omission for a personal repo.
• explain skill: description gains "Use when" phrasing (skill-check finding — quality score 70 → 100).

All 19 skills score 100/100 on skill-check; validate.sh, markdownlint, and shellcheck all pass locally.

🤖 Generated with Claude Code

Summary by CodeRabbit

• New Features

  • Integrated skill-check validation into the CI pipeline

• Documentation

  • Updated README with repository overview and workflow guidelines (ADR planning, issue implementation, refactoring)
  • Enhanced validation instructions with skill-check linting
  • Improved skill documentation with clearer descriptions

• Chores

  • Removed tessl CLI setup from development environments
  • Added skill-check configuration

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 253862c6-a0c0-419b-a1e2-3cbf4bc8e63a

📥 Commits

Reviewing files that changed from the base of the PR and between 17eb029 and c5e9bbe.

📒 Files selected for processing (6)

• .claude/hooks/session-start.sh
• .github/workflows/ci.yml
• README.md
• scripts/setup-env.sh
• skill-check.config.json
• skills/explain/SKILL.md

💤 Files with no reviewable changes (1)

• scripts/setup-env.sh

---

📝 Walkthrough

Walkthrough

This PR replaces Tessl CLI linting with skill-check. A new configuration file enables skill-check validation, the CI workflow integrates the new linting step, local setup scripts remove Tessl references, and documentation is updated to describe the new workflow and validation toolchain.

Changes

Tessl to Skill-Check Linting Migration

Layer / File(s)	Summary
Skill-check Configuration skill-check.config.json	New JSON configuration defines the project root, file patterns for skill markdown inclusion/exclusion, and disables frontmatter unknown fields validation.
CI Workflow Linting Steps .github/workflows/ci.yml	The validate job adds a new skill-check step before markdownlint and shellcheck, configured to skip security scanning, fail on warnings, and report in GitHub format.
Local Setup Script Updates .claude/hooks/session-start.sh, scripts/setup-env.sh	Tessl installation logic is removed; session-start comment clarifies setup runs only in remote environments; setup-env final guidance echoes only validate.sh, markdownlint-cli2, and shellcheck.
Documentation and Metadata README.md, skills/explain/SKILL.md	README adds a Workflows section outlining ADR planning, issue implementation, refactoring, and utilities; Validation section now includes npx skill-check with configuration notes; explain skill description updated to document walkthrough generation behavior.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the two main changes: documenting skill workflows and replacing tessl with skill-check. It is specific, concise, and clearly conveys the primary intent of the changeset.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch chore/readme-workflows-skill-check

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}