extending-services

extending-services is a cursor rule for Cursor from decagondev/MCP-Factory. It costs 0 tokens per session (1,062 once invoked), scanned A, original, no licence file.

Instructions for adding a new API service plugin to MCP Factory, a system for connecting agents to external services through a common interface.

In plain words
What is it for?
Use them when implementing a new API service plugin for MCP Factory.
Why use it?
They provide an ordered process for extending the factory without guessing how new services should be added.

Cursor rule for Cursor

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.

agentmods
npx agentmods add rules/decagondev/mcp-factory/extending-services
Clone the repo
git clone --depth 1 https://github.com/decagondev/MCP-Factory

Made for: Cursor.

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 extending-services

README.md
[![agentmods](https://agentmods.dev/badge/rules/decagondev/mcp-factory/extending-services.svg)](https://agentmods.dev/rules/decagondev/mcp-factory/extending-services)
Your own site
<a href="https://agentmods.dev/rules/decagondev/mcp-factory/extending-services"><img src="https://agentmods.dev/badge/rules/decagondev/mcp-factory/extending-services.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 1,062 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
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 $0.00000 $0.01062
Opus 5 $0.00000 $0.00531
Sonnet 5 $0.00000 $0.00212
Haiku 4.5 $0.00000 $0.00106

Measured 4d ago against content hash 313f4d79d280, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

extending-services scanned grade A with 1 finding 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 4d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

async def fetch(self, **params: str) -> dict[str, Any] | None:
.cursor/rules/extending-services.mdc · 141 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 4d ago First seen · 141 lines · 0 tokens per session scan A 313f4d79d280

Subscribe to this mod's changes

extending-services is a cursor rule published in the GitHub repository decagondev/MCP-Factory (7 stars, last pushed 1mo ago), with no licence file. It costs nothing until one of its globs matches a file; then it loads 1,062 tokens. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.