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mcp-builder

DEPRECATED: This skill has been replaced by `mcp-app-builder`. Check if `mcp-app-builder` is available in the skills folder. If not, install it: `npx skills install mcp-use/mcp-use --skill mcp-app-builder` Use `mcp-app-builder` instead of this skill. Build Model Context Protocol (MCP) servers with mcp-use framework. Use when creating MCP servers, defining tools/resources/prompts, working with mcp-use, bootstrapping MCP projects, or when user mentions MCP development, tools, resources, or prompts.

70

Quality

85%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

The canonical home for this skill is mcp-builder in CopilotKit/CopilotKit

SKILL.md
Quality
Evals
Security

Quality

Content

87%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

An exemplary overview file: token-lean, fully executable quick-reference code, and textbook progressive disclosure with real, well-triggered reference files. The one notable weakness is workflow clarity — the build flow (plan → implement → ship) has no validation or testing checkpoint for the produced server.

Suggestions

Add a final workflow step with a concrete verification action, e.g. 'After implementing, run the server and confirm each tool/resource/prompt is registered before delivering' — this would lift the missing checkpoint in the Before You Code → Implementation sequence.

Follow through on the 'Decide what needs UI vs text' step with an explicit decision checkpoint (e.g. one line stating when to choose a widget over a text response) rather than leaving it implicit in the linked reference.

Either show a minimal `widget()` usage inline or drop the unused `widget` import from the Quick Reference so the example remains exactly copy-paste runnable.

DimensionReasoningScore

Conciseness

The body is lean: a two-line design directive, four task-to-reference routing lines, one compact Quick Reference block, and two one-line API lists. No concept explanations Claude already knows, no padding — every section earns its tokens, matching the 'lean and efficient' 5 anchor.

5 / 5

Actionability

The Quick Reference is copy-paste-ready TypeScript with real imports, working tool/resource/prompt registrations, and `server.listen()`, covering the common cases; helper and server-method inventories are enumerated. The unused `widget` import has no inline example, but widgets are delegated to a dedicated reference file, so this is within the 5 anchor's 'specific examples cover the common cases'.

5 / 5

Workflow Clarity

A clear two-phase sequence exists (Before You Code: decompose and read design doc → Implementation: route by task type), but there are no checkpoints at all — no step to run or test the built server, verify tool schemas, or validate output. This matches the 3 anchor ('sequence present but checkpoints missing or implicit'); it is above 2 (sequence is well-defined, not rough) and below 4, which requires most checkpoints present.

3 / 5

Progressive Disclosure

The 80-line body is a pure overview: all five references/ files exist on disk, are linked one level deep, and each link carries an explicit 'when to read this' trigger (e.g. 'when writing server-side `server.tool()` code', 'when defining parameterized resources'). The Quick Reference inline code is appropriately sized for an overview, matching the 5 anchor's well-signaled one-level-deep structure.

5 / 5

Total

18

/

20

Passed

Description

83%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong description with an explicit capability statement and a well-formed 'Use when...' trigger clause covering multiple natural phrasings. The DEPRECATED preamble occupies most of the field's length and dilutes focus, and a few natural trigger variations are missing, but what/when are both explicit and concrete.

DimensionReasoningScore

Specificity

Explicitly states concrete actions: 'Build Model Context Protocol (MCP) servers with mcp-use framework', 'creating MCP servers, defining tools/resources/prompts', and 'bootstrapping MCP projects'. Matches the 'lists several specific actions; minor gaps in coverage' anchor — it omits concrete actions for the widgets/response-helpers capabilities the body actually covers — and is clearly above the 3 anchor, which expects only 1-2 concrete actions.

4 / 5

Completeness

Both halves are explicit: what — 'Build Model Context Protocol (MCP) servers with mcp-use framework'; when — 'Use when creating MCP servers, defining tools/resources/prompts, working with mcp-use, bootstrapping MCP projects, or when user mentions MCP development, tools, resources, or prompts'. This mirrors the 5 anchor's example almost exactly; the DEPRECATED preamble adds noise but does not weaken either half.

5 / 5

Trigger Term Quality

Natural triggers include 'MCP servers', 'MCP development', 'tools, resources, or prompts', 'bootstrapping', and the spelled-out 'Model Context Protocol (MCP)'. Good coverage, but common variations users might say (e.g. 'MCP client', 'model context', file extensions) are missing, so it fits the 4 anchor rather than the comprehensive 5.

4 / 5

Distinctiveness Conflict Risk

The 'mcp-use framework' / MCP-server-building niche is clearly distinct from generic skills, but the generic trailing phrase 'tools, resources, or prompts' and the coexistence with its own replacement ('Use `mcp-app-builder` instead of this skill') create minor overlap risk with a closely related skill — matching the 4 anchor, not the minimal-conflict 5.

4 / 5

Total

17

/

20

Passed

Validation

100%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
Shubhamsaboo/awesome-llm-apps
Reviewed

Table of Contents

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