Claude Skills
The open format is called Agent Skills and works in Claude Code, Codex, Cursor and other agents — most people know it as Claude Skills.
Every Agent Skill we could find on GitHub, deduplicated by content. 79 566 files from 1 758 authors, of which 61 913 are unique — the rest is the same skill repackaged into someone else's repository. For each one: what it weighs in tokens, whether it ships runnable scripts, and which MCP servers it needs.
Ecto patterns — schemas, changesets, queries, migrations, Multi, associations, preloads, upserts. Use when editing Repo calls, Ecto.Query, or schema fields. Skip for Ash.
Fetch HexDocs for Elixir libraries with HTML-to-markdown conversion. Use when looking up docs on hexdocs.pm — modules, functions, guides, changelogs.
OTP/BEAM patterns and Elixir idioms — GenServer, Supervisor, Task, Registry, pattern matching, with chains, pipes. Use when designing processes or debugging BEAM issues.
Inspect LiveView socket assigns for memory bloat — missing temporary_assigns, unused assigns, unbounded lists needing streams, memory estimates. Use when LiveView memory grows or you need to add temporary_assigns.
Build LiveView: async data (assign_async), PubSub (check connected?), phx-change events, form components/modals/uploads, streams for lists, live_patch. Use when handling interactions, debugging events, or tracking Presence.'
Route ambiguous or mixed Phoenix/LiveView/Ecto requests before choosing a workflow. Use when user is unsure where to start/how to approach work, asks for the right workflow, or combines intents such as fixing and refactoring. NOT for a clear task.
Narrow bare rescue in Elixir so real errors like KeyError and typos propagate instead of being swallowed. Use to audit rescues and refactor error handling.
Oban job processing — workers, perform/1 (OSS) and process/1 (Pro), queues, cron, retries, unique jobs, idempotency, Oban Pro (Workflow, Batch, Chunk, Smart Engine), Testing. Use when writing Oban workers, queue config, or debugging jobs.
Phoenix context design — creating/splitting contexts, Scope (1.8+), Ecto.Multi, PubSub, routers, plugs, controllers. Use when editing contexts, routers, or designing boundaries.
Analyze Phoenix context boundaries and module coupling via mix xref. Use when checking cross-context calls, validating dependencies, before splitting modules, or reviewing architecture.
Project health audit and health check — architecture, performance, tests, dependencies, code quality. Use when assessing overall project health, before releases, or after refactors.
Brainstorm Elixir/Phoenix features — explore ideas, compare approaches, gather requirements. Use when vague idea, not sure how to approach, or want to discuss before plan.
Fix Elixir/Phoenix code until Codex CLI review comes back clean — bounded review, fix, verify loop before opening a PR. Use when codex is installed and you want an external cross-model critic on your changes before pushing.
Challenge mode reviews - rigorous questioning before approving changes. Use when you want thorough scrutiny of Ecto changes, LiveView events, OTP designs, or PR readiness.
Interactive briefing of a plan file — explains reasoning, schema decisions, component choices. Use when developers need to understand a plan before approving.
Capture solved problems as searchable solution docs. Use after fixing bugs, when "that worked", or after successful phx-review or phx-investigate.
Audit Hex deps for supply-chain security risk — bidi chars, compile-time exec, maintainer changes, typosquats, CVEs. Use after mix deps.update, when checking if a package upgrade is safe, or reviewing mix.lock PR diffs.
Bump outdated Hex deps — inventory, snapshot changelogs, update, fix breaks, split reviewable PRs (patches bundled, majors solo). Use to upgrade/bump Elixir dependencies or when versions fall behind. NOT for deps.get failures (phx-investigate).
Record a vetted Hex package version in hex_vet.exs after a security review — manages the audit ledger, not the scanner. Use to approve a dep after phx-deps-audit findings or to initialize hex_vet.exs.
Apply an advisory edit scope in this session. Use for read-only or directory-scoped work; no enforcement hook is installed.
Run a portable sequential plan-work-verify-review-compound lifecycle. Use optional generic workers only when Amp makes them available.
Generate @moduledoc/@doc for tested Elixir features; may update their README section or ADR. Not for docs lookup, documentation audits/reviews, or capturing standalone decisions.
Choose Phoenix review, plan, debug, or test command. Use when user asks which phx-* command or plugin skill handles a task; do not route only to a domain skill. NEVER for bare /help; NOT for ambiguous requests (use intent-detection) or a plugin tour.
Initialize plugin in a project — install Iron Laws, auto-activation rules, and reference auto-loading into CLAUDE.md. Use when setting up or updating the plugin.
Walk through the Elixir/Phoenix plugin commands, workflow, and features in 6 interactive sections. Use when a new user wants to learn what the plugin offers or needs a refresher on available commands.
Investigate Elixir/Phoenix bugs root-cause first. Reproduce failures, cite evidence, and use optional Amp subagents only when useful.
Capture Elixir/Ecto/LiveView lessons and Hex API rules. Use after corrections or when asked to document learning, record a lesson, prevent a fixed mistake, or remember package guidance with --library.
Reduce mix output noise (5-15% token savings) by installing rtk filters that compress mix test/credo/dialyzer/compile output before it reaches Claude. Use when long mix output floods context.
Analyze Elixir/Phoenix performance — N+1 queries, assign bloat, ecto optimization, genserver bottlenecks. Use when slowness, timeouts, or high memory reported.
Recommend safe Bash permissions for Elixir mix commands in settings.json. Use when permission prompts slow workflow, "fix permissions", "reduce prompts", "auto-allow mix".
Plan features spanning multiple domains: billing (Stripe), auth (RBAC), real-time (Presence), webhooks, jobs (Oban). Use when designing interconnected systems or converting review findings into tasks.'
Address feedback left on a GitHub pull request: fetch unresolved review threads, make agreed Elixir/Phoenix code fixes, reply, and resolve. Use for a PR URL/number or reviewer comments. NOT for pre-PR review, findings triage, or CI monitoring.'
Implement small Phoenix changes without planning — add validations, update routes, fix components, create migrations. Use for single-file edits under 50 lines.
Recall prior work from past sessions — how a bug was fixed, what was decided, where a pattern lives. Use when asked 'have we done this before' or 'how did I fix X' in Elixir/Phoenix work. ccrider MCP when available, else git + solution docs.
Research Elixir/Phoenix/Ecto topics or evaluate Hex libraries (--library). Use when learning about libraries, patterns, or comparing approaches. Searches HexDocs, ElixirForum, GitHub.
Review changed Elixir/Phoenix code read-only. Check requirements, cite evidence, deduplicate findings, and return a severity-based verdict.
Analyze Elixir/Phoenix technical debt — duplicates, refactoring opportunities, credo issues. Use when asked about code quality, cleanup, or what to improve.
Trace Elixir call trees from entry points via mix xref. Use when debugging data flow, planning signature changes, or understanding how a bug reaches code.
Triage review findings interactively — approve, skip, or prioritize each issue. Use after phx-review to filter findings before fixing.
Verify Elixir/Phoenix changes — compile, format, and test in one loop. Use after implementation, before PRs, or after fixing bugs.
Watch an Elixir/Phoenix PR for new review comments (bot + human) and CI results via a background watcher that wakes Claude only on real events. Use after opening a PR or pushing, while waiting on CI or reviewers.
Execute Elixir/Phoenix plan tasks with progress tracking. Use after phx-plan to implement features with mix compile and mix test verification after each step, or --continue to resume interrupted work.
Enforce Elixir/Phoenix security — auth, OAuth, sessions, CSRF, XSS, SQL injection, input validation, secrets. Use when editing auth files, login flows, RBAC, or API keys.
Write or repair Elixir tests with ExUnit, sandbox isolation, async reliability, Mox, ExMachina, and LiveViewTest. Use for test files, test setup, or failing/flaky tests. NOT for investigating an application bug outside the test suite.
Ash Framework — resources, actions, policies, aggregates; Use when generating resources via mix ash.codegen, editing…
Tidewave MCP runtime tools — debugging, smoke testing, live state inspection, SQL queries, hex docs. Use when evaluating code in a running Phoenix app.
Searchable Elixir/Phoenix/Ecto solution documentation system with; Use when consulting past solutions…
Elixir/Phoenix deployment patterns — Dockerfile, fly.toml; Use when configuring Fly.io, Docker, CI/CD, health checks…
Debug Ecto constraint violations - trace triggers, check migrations; Use when seeing unique_constraint…
Find Ecto N+1 queries and missing preloads. Use only when N+1 is suspected; not for broad database performance.
Ecto patterns — schemas, changesets, queries, migrations, Multi; Use when editing Repo calls, Ecto.Query, or schema…
OTP/BEAM patterns and Elixir idioms — GenServer, Supervisor, Task; Use when designing processes or debugging BEAM…
Fetch HexDocs for Elixir libraries with HTML-to-markdown conversion. Use when looking up docs on hexdocs.pm…
Route ambiguous or mixed Phoenix/LiveView/Ecto requests; Use when user is unsure where to start/how to approach work…
Build LiveView: async data (assign_async), PubSub (check connected?); Use when handling interactions, debugging…'
Inspect LiveView socket assigns for memory bloat — missing; Use when LiveView memory grows or you need to add…
Narrow bare rescue in Elixir so real errors like KeyError and typos; Use to audit rescues and refactor error handling.
Oban job processing — workers, perform/1 (OSS) and process/1 (Pro); Use when writing Oban workers, queue config…
Phoenix context design — creating/splitting contexts, Scope (1.8+); Use when editing contexts, routers, or designing…
Brainstorm Elixir/Phoenix features — explore ideas, compare; Use when vague idea, not sure how to approach, or want…
Claude Skills — questions
Answers built from the skills we actually parsed.