Backend and APIs

19,593 mods in this category, of every kind an agent can take. Each one carries what it costs per session, what the scan found, and whether it is the original.

utcp-cli

73

universal-tool-calling-protocol/code-mode

Skill Claude CodeCodex

Call external APIs, MCP servers, and CLI tools by writing TypeScript code that runs in a sandbox — without MCP. Use when the user wants the agent to use a tool/API/integration (e.g. "search Open Library", "read my Notion", "call this REST API") in an environment that has a shell but no MCP config and no settable…

not rated 1.6k +23 2mo ago A SkillSpector: warn 146 tokens original MPL-2.0

n8n-architect

74

EtienneLescot/n8n-as-code

Skill Claude CodeCodex

Use when the user explicitly wants to create, edit, validate, sync, or troubleshoot n8n workflows, asks about n8n nodes or automation, or wants to use n8n-as-code in the current context root.

not rated 1.6k +6 changed 1mo ago A SkillSpector: warn 52 tokens original MIT

files-sdk

75

haydenbleasel/files-sdk

Skill Claude CodeCodex

Use files-sdk to add file storage to a TypeScript/JavaScript app with a unified API across 49 adapters (S3, R2, GCS, Azure, Vercel Blob, the local filesystem, and more). Triggers when the user wants to upload/download/list/search/move/delete/copy files, generate presigned URLs, do multipart or resumable uploads, range…

not rated 1.6k +1 changed 22d ago A SkillSpector: warn 306 tokens original MIT

fastcrud

76

benavlabs/fastcrud

Skill Claude CodeCodex

Use when building or modifying CRUD endpoints with FastCRUD (the fastcrud PyPI package) in a FastAPI project — covers FastCRUD, crudrouter, EndpointCreator, FilterConfig, JoinConfig, auto-relationship detection, the filter operator syntax (gte, in, ilike, etc.), cursor pagination, soft delete, and how to avoid N+1…

not rated 1.6k changed 25d ago A SkillSpector: warn 147 tokens original MIT

moq

77

moq-dev/moq

Skill Claude CodeCodex

Build live video, audio, and real-time data apps with Media over QUIC (MoQ). Use when adding live streaming, conferencing, voice AI, or real-time pub/sub to an app; when integrating the @moq/ npm packages, moq- Rust crates, or the Python/Kotlin/Swift/Go/C/Dart bindings; or when running a moq-relay server or a gateway…

not rated 1.6k +9 changed 15d ago A SkillSpector: pass 106 tokens original Apache-2.0

superlog

79

superloglabs/superlog

MCP server Claude CodeCodexCursor +2

Open-source agent that observes and fixes your application. Query logs, traces, metrics, incidents. Remote server at api.superlog.sh.

not rated 1.5k +3 3d ago A tokens not measured original Apache-2.0

backend

80

nixopus/nixopus

Cursor rule Cursor

Go API Development Rules for Nixopus Backend.

not rated 1.5k +1 5d ago A 0 tokens

atsign-foundation/at_client_sdk

Skill Claude Code

Use this skill when a developer builds or upgrades a Dart or Flutter app on the Atsign Protocol with atclientcli (CLI, daemon or server) or atclientflutter, including upgrading to atclient 4.0. Covers onboarding (CRAM, atKeys files, keychain) and APKAM enrollment; opening, stopping or switching an AtClient and its…

not rated 1.4k +1 changed yesterday A SkillSpector: warn 220 tokens original BSD-3-Clause

WhiteNightShadow/hello_js_reverse_skill

Skill Claude CodeCodex

A skill for analysing and reproducing web API request signatures for platforms you own or are authorised to use, using Node.js or Python. It also covers browser debugging and protected JavaScript analysis.

not rated 1.4k +14 changed today A 182 tokens

HashLoad/horse

Skill Claude CodeCodex

Guide for setting up thread-safe database connection pooling (FireDAC / UniDAC) in multithreaded Horse applications.

not rated 1.4k +1 8d ago A SkillSpector: pass 30 tokens original MIT

xurl

85

xdevplatform/xurl

Skill Claude CodeCodex

A curl-like CLI tool for making authenticated requests to the X (Twitter) API. Use this skill when you need to post tweets, reply, quote, search, read posts, manage followers, send DMs, send or read end-to-end encrypted XChat messages, upload media, or interact with any X API v2 endpoint. Supports multiple apps, OAuth…

not rated 1.4k +1 1mo ago A 92 tokens original MIT

claude-api

86

Prismer-AI/PrismerCloud

Skill Claude CodeCodex

Build, debug, and optimize Claude API / Anthropic SDK apps. Apps built with this skill should include prompt caching. Also handles migrating existing Claude API code between Claude model versions (4.5 → 4.6, 4.6 → 4.7, retired-model replacements). TRIGGER when: code imports anthropic/@anthropic-ai/sdk; user asks for…

not rated 1.4k +1 changed 1mo ago A SkillSpector: warn 193 tokens original MIT

hesreallyhim/a-list-of-claude-code-agents

Agent Claude Code

Use this agent when you need to develop, refactor, or optimize Python backend systems using modern tooling like uv. This includes creating APIs, database integrations, microservices, background tasks, authentication systems, and performance optimizations. Examples: Context: User needs to create a FastAPI application…

not rated 1.4k +1 12mo ago A 252 tokens

setup-rate-limiting

88

qdhenry/Claude-Command-Suite

Command Claude Code

Command "setup-rate-limiting" from qdhenry/Claude-Command-Suite, covering setup rate limiting and instructions.

not rated 1.3k +2 8mo ago A 0 tokens

wordpress-skill

89

uluckyXH/OpenMOSS

Skill Claude CodeCodex

A command-line tool for managing a WordPress website's posts, pages, media, categories, tags, and search results. WordPress is a content-management system for publishing websites.

not rated 1.3k +8 4mo ago A SkillSpector: pass 29 tokens original MIT

FabricAppDev

90

microsoft/skills-for-fabric

Agent Claude Code ✓ vendor

Build full-stack applications on top of Microsoft Fabric using Python, ODBC, XMLA, and REST APIs. Use when the request involves building applications connected to Fabric data. Delegates endpoint-specific implementation to specialized skills.

not rated 1.3k +20 yesterday A 48 tokens original MIT

channel-extension

91

Dpro-at/Tel-Agent

Skill Claude Code

Use when adding a new messaging channel to Tel-Agent or changing an existing one — a transport under api/channels/, its official extension manifest, its settings card, tests, health and docs. Covers the file checklist, the two inbound shapes (dial-out and the public door), the credential and signature rules that are…

not rated 1.2k +15 changed 1mo ago A 89 tokens AGPL-3.0

channels

92

ModalityDance/PalmClaw

Skill Claude CodeCodex

Configure per-session remote channels (Telegram/Discord/Slack/Feishu/Email/WeCom), then verify inbound/outbound routing and processing visibility.

not rated 1.2k +4 16d ago A SkillSpector: pass 32 tokens AGPL-3.0

mongodb-js/mongodb-mcp-server

Skill Claude CodeCodex

Migrates external consumer code from the mongodb-mcp-server v1/v2 single-package API to the v3 scoped-package structure. In v3, mongodb-mcp-server is a binary-only package (npx / MCPB); library embedding uses @mongodb-js/mcp-cli, @mongodb-js/mcp-core, @mongodb-js/mcp-http-runners, @mongodb-js/mcp-tools-, and the other…

not rated 1.2k +3 changed 1mo ago A SkillSpector: warn 153 tokens original Apache-2.0

backend-integrator

95

massgen/MassGen

Skill Claude CodeCodex

Complete guide for integrating a new LLM backend into MassGen. Use when adding a new provider (e.g., Codex, Mistral, DeepSeek) or when auditing an existing backend for missing integration points. Covers all 15 files that need touching.

not rated 1.1k +3 4mo ago A 57 tokens

sync-api-endpoints

96

jamro/tiny-engineer

Cursor rule Cursor

When HTTP routes change, update the web UI API page and API docs together.

not rated 1.1k +94 changed 23d ago A 0 tokens original

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