build-mcp-server

build-mcp-server is a skill for Claude Code from fuxicodex/Fuxi. It costs 113 tokens per session (2,811 once invoked), scanned A, original, no licence file.

A guided workflow for building an MCP server. MCP, or Model Context Protocol, is a standard way for an AI assistant to use tools and data from other programs.

In plain words
What is it for?
Creating an MCP integration, exposing tools, or wrapping an API for FuXi.
Why use it?
It helps turn an API or other service into tools that an AI assistant can access.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the mcp-server-dev plugin — 3 skills shipped together

Good fit Creating an MCP integration, exposing tools, or wrapping an API for FuXi.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/fuxicodex/fuxi/build-mcp-server
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add fuxicodex/Fuxi --skill build-mcp-server
Clone the repo
git clone --depth 1 https://github.com/fuxicodex/Fuxi

Made for: Claude Code.

Or install mcp-server-dev, the plugin that ships this one along with the rest of its 3 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for build-mcp-server

README.md
[![agentmods](https://agentmods.dev/badge/skills/fuxicodex/fuxi/build-mcp-server/github.svg)](https://agentmods.dev/skills/fuxicodex/fuxi/build-mcp-server)
Your own site
<a href="https://agentmods.dev/skills/fuxicodex/fuxi/build-mcp-server"><img src="https://agentmods.dev/badge/skills/fuxicodex/fuxi/build-mcp-server/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for build-mcp-server

Your own site · 80×15
<a href="https://agentmods.dev/skills/fuxicodex/fuxi/build-mcp-server"><img src="https://agentmods.dev/badge/skills/fuxicodex/fuxi/build-mcp-server.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 113 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,811 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00113 $0.02811
Opus 5.5 $0.00045 $0.01124
Sonnet 5 $0.00023 $0.00562
Haiku 4.5 $0.00011 $0.00281

Measured 5d ago against content hash c7f8cae70f27, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-28, from the pricing page.

Security

Grade A, and why

build-mcp-server scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

fuxi-marketplace/plugins/fuxi-plugins/plugins/mcp-server-dev/skills/build-mcp-server/SKILL.md · 222 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Files

What ships with it

8 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 222 lines · 113 tokens per session scan A c7f8cae70f27

Subscribe to this mod's changes

build-mcp-server is a skill published in the GitHub repository fuxicodex/Fuxi (3,363 stars, last pushed 4d ago), with no licence file. It adds 113 tokens to every session and 2,811 once invoked, about $0.0005 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-24.

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