Open a board in the app

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only declare readOnlyHint and openWorldHint=false; the description adds meaningful behavioral detail the annotations do not cover: that Mapache may be started if not running, that the board is not modified, and that the return value is the address. This is good added context, though it doesn't detail failure modes or timing.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tightly packed sentences, front-loaded with the core action and scope, then the suggested use and the launch nuance. Every clause carries information with no padding.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read-only, zero-required-parameter tool with no output schema, the description covers purpose, effect boundary, side effect (starting the app), and return value. Nothing an agent needs to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so both parameters are already documented in the schema, and the enum-like value 'open' for board is defined there. The description restates the launch=false behavior but adds no new syntax or format detail beyond the schema, so baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (open), resource (a board), the surface it opens in (the person's browser, starting Mapache if needed), and the effect boundary ('it does not change the board'). This clearly separates it from read_board and export_board.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives concrete usage guidance: 'Offer it after a big change; set launch to false to only get the link.' This tells the agent when to invoke it and how to get link-only behavior. It stops short of naming an explicit alternative (e.g., read_board for content vs. open for viewing), leaving minor inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.