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.
npx agentmods add rules/ekakit/lightfast-mcp/mcp-conceptsgit clone --depth 1 https://github.com/ekakit/lightfast-mcpWrote 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.
[](https://agentmods.dev/rules/ekakit/lightfast-mcp/mcp-concepts)<a href="https://agentmods.dev/rules/ekakit/lightfast-mcp/mcp-concepts"><img src="https://agentmods.dev/badge/rules/ekakit/lightfast-mcp/mcp-concepts.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00259 | $0.00259 |
| Opus 5 | $0.00130 | $0.00130 |
| Sonnet 5 | $0.00052 | $0.00052 |
| Haiku 4.5 | $0.00026 | $0.00026 |
Grade A, and why
mcp-concepts 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 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.
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.
What it actually says
MCP Core Concepts
This is lightfast-mcp, a Model Context Protocol (MCP) implementation for creative applications like Blender. Remember these key concepts:
MCP Protocol Fundamentals
- MCP Server: Exposes tools and resources through standardized protocol (this project implements servers)
- MCP Client: Connects to servers to use tools (AI models use clients)
- Transport Types:
stdio(local subprocess) orsse(HTTP Server-Sent Events) - Tools: Functions that can be called by AI models with
@mcp.tool()decorator - Resources: Data sources that can be read by AI models with
@mcp.resource()decorator - Prompts: Reusable prompt templates with parameters
Project Context
- We implement MCP servers for creative applications
- FastMCP library provides the
@mcp.tool()and@mcp.resource()decorators - All servers inherit from
BaseServerand useServerConfig - Support both
stdioandstreamable-httptransports - Configuration-driven design using YAML/JSON config files
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.
- 4d ago First seen · 24 lines · 259 tokens per session scan A 3d6f3cb8a574
mcp-concepts is a cursor rule published in the GitHub repository ekakit/lightfast-mcp (2 stars, last pushed 1y ago), licensed MIT. It adds 259 tokens to every session, about $0.0013 per session on Opus 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 2026-08-31.
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