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fastmcp-client-cli

Query and invoke tools on MCP servers using fastmcp list and fastmcp call. Use when you need to discover what tools a server offers, call tools, or integrate MCP servers into workflows.

Quality

91%

Does it follow best practices?

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SecuritybySnyk

Low

Low-risk findings worth noting

SKILL.md
Quality
Evals
Security

Quality

Content

96%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 excellent single-file CLI reference: fully executable commands, lean prose that only adds non-obvious behavior, and an explicit discover-list-call workflow with an error-recovery hint. The only structural note is that everything lives inline at ~110 lines with no reference files, which is acceptable but just short of ideal progressive disclosure.

DimensionReasoningScore

Conciseness

The body is lean: every prose sentence adds non-obvious CLI behavior ('Type coercion is automatic: limit=5 becomes an integer', 'HTTP targets automatically use OAuth'), and it never explains concepts Claude already knows like what MCP is. Matches the anchor 'every token earns its place'.

5 / 5

Actionability

All examples are fully executable, copy-paste-ready commands covering the common cases: multiple server targets, key=value and JSON argument styles, --input-json overrides, --json output, and discover/auth flags. Matches anchor 5.

5 / 5

Workflow Clarity

The 'Workflow Pattern' section explicitly sequences discover -> list -> call with an error-recovery note ('If you call a nonexistent tool, FastMCP suggests close matches'). This is not a destructive or batch skill, so the validation cap does not apply, and the workflow is unambiguous.

5 / 5

Progressive Disclosure

Well-organized sections (Listing Tools, Calling Tools, Server Targets, Auth, Discovering Configured Servers, Workflow Pattern) with no buried or nested references. It is not 5 because the ~110-line body inlines everything (e.g., the Server Targets table and Auth details) with no one-level-deep reference split, and the under-50-line simple-skill exception does not apply.

4 / 5

Total

19

/

20

Passed

Description

82%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 that clearly states what the skill does (query and invoke MCP tools via fastmcp list/call) and when to use it, with natural trigger terms and a distinct niche. The main flaw is the second-person voice ('Use when you need to...'), which the rubric penalizes on specificity.

Suggestions

Rewrite the trigger clause in third person to match the rubric's voice requirement, e.g., 'Use when the user needs to discover what tools a server offers, call tools, or integrate MCP servers into workflows.'

Broaden the 'what' coverage slightly by mentioning server discovery (fastmcp discover) and auth handling alongside list/call, so the capability list is more comprehensive.

DimensionReasoningScore

Specificity

Names the domain and concrete actions ('Query and invoke tools on MCP servers using fastmcp list and fastmcp call'), which fits anchor 4, but the second-person trigger clause ('Use when you need to...') incurs the rubric's mandatory -1 penalty on specificity, dropping it to 3. It is not anchor 2 because the actions and commands are specific rather than generic.

3 / 5

Completeness

Explicitly answers both: what ('Query and invoke tools on MCP servers using fastmcp list and fastmcp call') and when ('Use when you need to discover what tools a server offers, call tools, or integrate MCP servers into workflows') with concrete trigger phrases, matching the anchor-5 example pattern.

5 / 5

Trigger Term Quality

Good natural keyword coverage: 'MCP servers', 'discover what tools a server offers', 'call tools', 'integrate MCP servers into workflows'. A few natural terms are missing (e.g., 'Model Context Protocol' spelled out, 'list tools'), so it is not the comprehensive anchor 5, but it clearly exceeds anchor 3's partial coverage.

4 / 5

Distinctiveness Conflict Risk

Clear niche (fastmcp CLI for MCP server tool discovery and invocation) with distinct trigger terms; minimal conflict risk with other skills, matching anchor 5.

5 / 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

PrefectHQ/fastmcp

Path

skills/fastmcp-client-cli/SKILL.md

Reviewed

Table of Contents

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