What is tool-discovery?

A guide for finding out which coding tools, browser features, canvases, and connected services are available in the current environment before using them.

Tool-heavy coding sessions, unfamiliar environments, browser or canvas work, and tasks involving MCP services, which let an agent call external tools.

It prevents the agent from assuming a tool exists or using the wrong input format for a connected service.

tool-discovery — Cursor rule for Cursor by madebyaris

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.

Clone the repo

git clone --depth 1 https://github.com/madebyaris/advance-minimax-m3-cursor-rules

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.

README.md

[![agentmods](https://agentmods.dev/badge/rules/madebyaris/advance-minimax-m3-cursor-rules/tool-discovery/github.svg)](https://agentmods.dev/rules/madebyaris/advance-minimax-m3-cursor-rules/tool-discovery)

Your own site

<a href="https://agentmods.dev/rules/madebyaris/advance-minimax-m3-cursor-rules/tool-discovery"><img src="https://agentmods.dev/badge/rules/madebyaris/advance-minimax-m3-cursor-rules/tool-discovery/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.

Your own site · 80×15

<a href="https://agentmods.dev/rules/madebyaris/advance-minimax-m3-cursor-rules/tool-discovery"><img src="https://agentmods.dev/badge/rules/madebyaris/advance-minimax-m3-cursor-rules/tool-discovery.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 41 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 791 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 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.

Model	Per session	Once invoked
Fable 5.1	$0.00041	$0.00791
Opus 5	$0.00020	$0.00396
Sonnet 5	$0.00008	$0.00158
Haiku 4.5	$0.00004	$0.00079

Measured 11d ago against content hash ab5c4f26ed22, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

tool-discovery 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 11d 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.

.cursor/rules/tool-discovery.mdc · 70 lines

How it starts

The opening of the file, as written. The whole thing — 70 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Tool Discovery (Cursor 3.7 + M3)

Current through Cursor 3.7 (Jun 2026). Use this rule when the runtime surface is unfamiliar, tool-heavy, or likely to differ across environments.

Discovery Order

Inventory the current surface in this order:

direct tools exposed in the prompt (Read, Grep, Task, Await, etc. — names vary by surface; the live list wins)
browser, canvas, and other IDE-native surfaces exposed in the prompt
- Browser MCP (cursor-ide-browser): snapshot-first automation; read the server's tool descriptors
- Canvas (.canvas.tsx): confirm the session supports canvases before promising one; load the canvas skill before authoring
- Design Mode (3.7): user-driven in browser or canvas — not an agent tool; when the user has selected or annotated elements, treat that as the primary input for UI edits
Cursor Marketplace (or team marketplace) plugins already installed — same schema-first rules as other MCPs; discover tools and resources from each plugin's descriptors before calling
MCP tools and resources with their current schemas (including project-configured servers under the session's MCP descriptor path)
web docs only when discovery or versions still remain unclear

For delegation, read the live Task schema for available subagent_type values and whether nesting or run_in_background applies (Multitask Mode expects background runs).

Schema-First Use

Read the current schema or descriptor before calling unfamiliar MCP tools.
Match the task step to the smallest tool that can honestly do it.
Do not infer hidden parameters or old wrapper names from memory.
MCP Apps structured content: when a tool returns structured content, prefer the structured form over reconstructing from prose. When the structured data is the deliverable, route it to a canvas rather than a markdown table in chat.

Capability Mapping

Before acting, translate the task into:

what must be read
what must be changed
what must be verified
which currently exposed tool best serves each step

Read the full file on GitHub · 70 lines

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.

11d ago First seen · 70 lines · 41 tokens per session scan A ab5c4f26ed22

Subscribe to this mod's changes

tool-discovery is a cursor rule published in the GitHub repository madebyaris/advance-minimax-m3-cursor-rules (125 stars, last pushed 2mo ago), licensed MIT. It adds 41 tokens to every session and 791 once invoked, about $0.0002 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 2026-08-30.

Building agents Code Generation agentic-ai ai-coding ai-workflow cursor cursor-ide

git-commit

Use this when the user asks for a git commit, commit message, or commit command.

kyungseo/ai-workflow-harness · 18 tokens

learnship

Activate learnship agentic engineering workflows — structured phases, persistent memory, learning partner, and impeccable UI design. Use whenever a user is working on a software project or asks about project planning, phases, workflows, or how to build something.

FavioVazquez/learnship · 48 tokens

tool-discovery