{"id":50418954,"url":"https://github.com/paulieb89/fastmcp-builder-template","last_synced_at":"2026-05-31T07:30:41.039Z","repository":{"id":356496958,"uuid":"1231489653","full_name":"paulieb89/fastmcp-builder-template","owner":"paulieb89","description":"FastMCP v3 template for building and reviewing MCP servers (incl. build loop)","archived":false,"fork":false,"pushed_at":"2026-05-08T11:03:57.000Z","size":191,"stargazers_count":0,"open_issues_count":0,"forks_count":0,"subscribers_count":0,"default_branch":"main","last_synced_at":"2026-05-08T11:32:17.910Z","etag":null,"topics":["ai-agents","anthropic","claude-code","fastmcp","mcp","model-context-protocol","pydantic","python","template","uv"],"latest_commit_sha":null,"homepage":"","language":"Python","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"mit","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/paulieb89.png","metadata":{"files":{"readme":"README.md","changelog":"CHANGELOG.md","contributing":"CONTRIBUTING.md","funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null,"zenodo":null,"notice":null,"maintainers":null,"copyright":null,"agents":"AGENTS.md","dco":null,"cla":null}},"created_at":"2026-05-07T02:28:07.000Z","updated_at":"2026-05-08T11:06:07.000Z","dependencies_parsed_at":null,"dependency_job_id":null,"html_url":"https://github.com/paulieb89/fastmcp-builder-template","commit_stats":null,"previous_names":["paulieb89/fastmcp-builder-template"],"tags_count":2,"template":true,"template_full_name":null,"purl":"pkg:github/paulieb89/fastmcp-builder-template","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/paulieb89%2Ffastmcp-builder-template","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/paulieb89%2Ffastmcp-builder-template/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/paulieb89%2Ffastmcp-builder-template/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/paulieb89%2Ffastmcp-builder-template/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/paulieb89","download_url":"https://codeload.github.com/paulieb89/fastmcp-builder-template/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/paulieb89%2Ffastmcp-builder-template/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":33723548,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-05-26T15:22:16.424Z","status":"online","status_checked_at":"2026-05-31T02:00:06.040Z","response_time":95,"last_error":null,"robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":true,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["ai-agents","anthropic","claude-code","fastmcp","mcp","model-context-protocol","pydantic","python","template","uv"],"created_at":"2026-05-31T07:30:39.850Z","updated_at":"2026-05-31T07:30:41.031Z","avatar_url":"https://github.com/paulieb89.png","language":"Python","funding_links":[],"categories":[],"sub_categories":[],"readme":"# FastMCP Builder Template\n\n[![CI](https://github.com/paulieb89/fastmcp-builder-template/actions/workflows/ci.yml/badge.svg)](https://github.com/paulieb89/fastmcp-builder-template/actions/workflows/ci.yml)\n\nA Claude Code plugin **and** a learning template for [FastMCP v3](https://gofastmcp.com).\nSame repository, two consumers. The plugin **audits** existing FastMCP servers\nagainst the MCP protocol and FastMCP framework specs; the template gives a\nworked example to learn from.\n\n## How to read this README\n\nPick the use case that matches what you're trying to do.\n\n- **I want to install it as a plugin so Claude Code can audit my FastMCP servers** → [Install as a plugin](#install-as-a-plugin)\n- **I'm starting a new FastMCP server and want a worked example** → [Use as a learning template](#use-as-a-learning-template)\n- **I want to contribute to this repo** → [Contributing](CONTRIBUTING.md)\n\n---\n\n## What the plugin can do\n\nWhen installed, the plugin gives Claude Code five **automatic** deterministic\nchecks on every FastMCP server review, plus a set of **on-demand** helpers\nfor authoring new primitives.\n\n### Automatic checks (every review)\n\nEach finding cites the MCP/FastMCP spec section it enforces. Severity follows\nthe source: HIGH = protocol non-compliance; MEDIUM = framework recommendation.\n\n| Check | What it catches | Severity | Spec source |\n|---|---|---|---|\n| `review_fastmcp_manifest` | Missing names, malformed URIs, bad input schemas, duplicate primitive names, opaque descriptions | HIGH / MEDIUM | MCP + FastMCP |\n| `check_silent_error_returns` | `@mcp.tool` functions that return `{\"error\": ...}` or `\"Error: ...\"` instead of raising | HIGH | FastMCP `servers/tools.md#error-handling` |\n| `check_resource_mime_type_declared` | `@mcp.resource` decorators without `mime_type=` | MEDIUM | FastMCP `servers/resources.md` |\n| `check_prompt_argument_descriptions` | `@mcp.prompt` arguments with no description (in docstring `Args:` block or `Annotated[..., Field(...)]`) | MEDIUM | MCP `server/prompts` |\n| `check_tool_annotations_declared` | `@mcp.tool` decorators missing the four standard `ToolAnnotations` hints | MEDIUM | MCP `server/tools#annotations` |\n\n### On-demand tools (call them when designing a new primitive)\n\nThese don't auto-fire; the plugin exposes them as MCP tools you can invoke\nexplicitly when authoring or reviewing one specific name/URI/description.\n\n- `classify_mcp_primitive` — should this capability be a tool, resource, or prompt?\n- `suggest_tool_contract` / `suggest_resource_contract` / `suggest_prompt_contract` — generate a starter contract from a description\n- `generate_minimal_server_plan` — scaffold a minimal FastMCP server plan\n- `check_tool_name_format` / `check_prompt_name_format` — validate a single name\n- `check_uri_stability` — check one URI pattern for volatile tokens\n- `check_tool_description_quality` — review one description\n- `check_error_response_design` — categorize a tool's failure modes (opinion-class, not a spec rule)\n- `extract_manifest_from_source` — parse a `.py` file → manifest dict (used internally by the design review skill)\n\n### Slash commands\n\n- `/design-fastmcp` — design a new FastMCP server before writing code\n- `/add-tool` — add one tool to an existing server with a typed contract\n- `/review-manifest` — review a manifest JSON against the spec\n\n### Skills (auto-activated when matching prompts)\n\n- `fastmcp-design-review` — audit an existing server (runs the automatic checks above)\n- `fastmcp-scaffold-author` — start a new FastMCP server from scratch\n- `fastmcp-build-loop` — implement a server from a spec file, one section at a time\n- `mcp-primitive-classification` — decide tool / resource / prompt for a new capability\n\n### Bundled learning material (resources)\n\nThe plugin exposes its bundled docs as MCP resources at `fastmcp-builder://docs/{slug}`:\n\n`mcp-primitives` · `tool-design` · `resource-design` · `prompt-design` ·\n`fastmcp-patterns` · `safety-boundaries` · `claude-code-workflow` ·\n`raw-mcp-to-fastmcp-v3`\n\nPlus a snapshot of the official FastMCP topic index at `docs/upstream/fastmcp-llms.md`\n(35 KB, refresh with `bash scripts/refresh-fastmcp-docs.sh` before tagging a release).\n\n---\n\n## What the plugin can't do\n\nHonest list of out-of-scope items so you know when to reach for something else.\n\n- **Doesn't run target servers.** Pure static AST analysis. Won't catch runtime\n  bugs, env-var misconfiguration, network errors, or anything that only\n  appears at execution time. If you need runtime checks, install the target\n  server and exercise it.\n- **Doesn't apply fixes.** Reports findings only. Claude (or you) reads the\n  report and edits the source. There is no `--fix` mode.\n- **FastMCP-specific.** Doesn't audit raw `mcp` SDK code, TypeScript MCP\n  servers, or other frameworks. The decorator patterns (`@mcp.tool`,\n  `@mcp.resource`, `@mcp.prompt`) and the `from fastmcp import FastMCP`\n  import path are baked into the AST walker.\n- **One server at a time.** No fleet/batch mode. Reviewing 12 servers means\n  invoking the skill 12 times.\n- **No fleet/personal conventions.** Checks are grounded in MCP/FastMCP spec\n  citations only. Style preferences (snake_case prefixes, single-input-model\n  patterns, pagination shapes) aren't enforced.\n- **AST limits.** Can't see through dynamic constructs — a `mime_type=` whose\n  value is a constant defined elsewhere in the module gets the benefit of\n  the doubt; a docstring built at runtime won't be analysed.\n- **Citation URLs are spec-section approximations.** They point at the\n  relevant page+anchor on `gofastmcp.com` / `modelcontextprotocol.io`, but\n  exact wording can shift between spec versions. Refresh the bundled\n  snapshot to validate.\n- **Bundled docs go stale.** The snapshot at `docs/upstream/fastmcp-llms.md`\n  is a point-in-time copy. The skill body instructs Claude to WebFetch the\n  live URL when the snapshot doesn't cover a topic.\n- **Doesn't deploy, monitor, or test.** Design-layer only. Use your existing\n  ops tooling for hosting and observability.\n\n---\n\n## Install as a plugin\n\nTwo install paths — pick whichever fits your Claude Code setup.\n\n**Via marketplace tab:**\n\n```text\nhttps://github.com/paulieb89/fastmcp-builder-template\n```\n\nPaste into the Marketplaces tab → Add. Then install the `fastmcp-builder`\nplugin from the Plugins tab.\n\n**Via slash command:**\n\n```text\n/plugin install https://github.com/paulieb89/fastmcp-builder-template\n```\n\n**Prerequisites:** `uv` on `$PATH`. The plugin runs its MCP server with\n`uv run --project ${CLAUDE_PLUGIN_ROOT} …`.\n\n**Verify it loaded:**\n\n```text\n/mcp\n```\n\nYou should see a server named `plugin:fastmcp-builder:srv` with ~15 tools.\nSkill triggers like \"review my MCP server\" will activate\n`fastmcp-design-review` automatically.\n\n---\n\n## Use as a learning template\n\nThe repo also functions as a clonable starter. Nothing about the plugin\nprevents you from treating it as a reference implementation.\n\n**To learn the patterns:**\n\n1. Clone the repo.\n2. Read `examples/notes_server.py` — a complete, passing-every-check FastMCP\n   server (~120 lines: two resources, one tool, one prompt).\n3. Read `docs/mcp-primitives.md` and `docs/tool-design.md` for the\n   primitive-design rationale.\n4. Adapt `notes_server.py` into your own server module.\n\n**To start fresh:**\n\n1. `uv sync` to install deps (`fastmcp==3.2.4`, `pydantic\u003e=2.7`).\n2. Write your server module.\n3. Run it: `uv run fastmcp run path/to/your_server.py:mcp`.\n4. If you want the plugin's audit on your work, install it as a plugin\n   (above) and ask Claude Code: *\"review the FastMCP design of `\u003cyour-server.py\u003e`\"*.\n\n---\n\n## How the two views share the repo\n\n| Path | Plugin uses | Template uses |\n|---|---|---|\n| `src/fastmcp_builder/` | ✅ (Python source — the MCP server) | ❌ |\n| `.claude-plugin/` | ✅ (manifest + marketplace entry) | ❌ |\n| `skills/`, `commands/` | ✅ (auto-discovered) | ❌ |\n| `examples/notes_server.py` | ✅ (test fixture + resource exposed via `fastmcp-builder://examples/`) | ✅ (clone-and-adapt reference) |\n| `docs/*.md` | ✅ (curated learning material, served as MCP resources) | ✅ (read directly) |\n| `docs/upstream/fastmcp-llms.md` | ✅ (spec snapshot for the design-review skill) | ✅ (FastMCP topic index) |\n| `tests/`, `pyproject.toml`, `.github/` | ❌ | ❌ |\n\nThe single integration test `tests/test_every_finding_has_citation.py` keeps\nthe two honest: it asserts every plugin check produces findings with non-None\n`spec_source`, AND that the bundled `notes_server.py` example passes every\nauto-fired check. If you change either side, the other has to follow.\n\n---\n\n## Local boundaries (out of scope, by design)\n\nThis template excludes:\n\n- Runtime network calls in the plugin's own code paths\n- Arbitrary shell execution tools\n- Databases, auth systems, hosted UIs\n- Crawlers, scrapers, vector databases, background jobs\n\nThe plugin's MCP server runs locally via STDIO. The only network call it\nmakes is the optional WebFetch the design-review skill does against\n`gofastmcp.com` when the bundled snapshot doesn't cover a topic.\n\n---\n\n## Contributing\n\nSee [CONTRIBUTING.md](CONTRIBUTING.md) for development setup, scope rules,\nrelease checklist, and PR guidelines. The repo has CI (pytest + ruff) on\nevery PR.\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fpaulieb89%2Ffastmcp-builder-template","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fpaulieb89%2Ffastmcp-builder-template","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fpaulieb89%2Ffastmcp-builder-template/lists"}