index

A central rule index for a project’s Cursor and Claude Code instructions. Cursor is a coding editor, while Claude Code is a coding assistant; the index points them to rules stored in a separate documentation folder.

In plain words
What is it for?
Use it to guide agents working in the observability monorepo, a repository that contains multiple related projects, especially before code changes.
Why use it?
It stops agents from searching the wrong folders or copying duplicate rules. It also tells them which architecture, typing, testing, commit, and security rules to read before changing code.

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/traceorb/obs-mcp/index
Clone the repo
git clone --depth 1 https://github.com/TraceOrb/obs-mcp

Made for: Cursor.

Per session 429 This file is loaded in full into every session.
When invoked 429 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original 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 $0.00429 $0.00429
Opus 5 $0.00215 $0.00215
Sonnet 5 $0.00086 $0.00086
Haiku 4.5 $0.00043 $0.00043

Measured yesterday against content hash 762d0bdae7f9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

index 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 yesterday.

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.

.cursor/rules/index.mdc · 32 lines

What it actually says

Rule index (mandatory)

.cursor/rules/ and .claude/rules/ contain only this file. Every other rule lives in obs-docs. Do not look for rules under these folders besides the index. Do not copy rules into .ai-rules/.

The Cursor workspace is the parent folder observability. Read with that path. If this repo is open alone, prefix with ../.

Before writing or changing code: Read the always-on files below. Then, if the task matches a row, Read that file too. Do not Read the rest.

Always — Read these now (every task)

File What it enforces
obs-docs/05-architecture/dev/rules/code-style-rules.md Mappers, no comments, no ternary, no else
obs-docs/05-architecture/dev/rules/typing-rules.md Strict TS, no any, no as, closed Record
obs-docs/05-architecture/dev/rules/testing-rules.md Spec for new or changed behavior
obs-docs/05-architecture/dev/rules/commit-rules.md Conventional Commits; agent commits, person publishes
obs-docs/05-architecture/dev/rules/security-rules.md Org isolation; read key only reads; MCP never sees ClickHouse

On demand — Read only if the task matches

When you are… Read
Adding or changing an MCP tool obs-docs/docs/superpowers/specs/2026-08-22-read-key-mcp-design.md
Publishing the package or changing CI obs-docs/05-architecture/dev/rules/deployment-rules.md

If two on-demand rows match, Read both. If none match, stop after the always-on files.

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. yesterday First seen · 32 lines · 429 tokens per session scan A 762d0bdae7f9

Subscribe to this mod's changes

index is a cursor rule published in the GitHub repository TraceOrb/obs-mcp (1 stars, last pushed 7d ago), licensed MIT. It adds 429 tokens to every session, about $0.0021 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.