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

Annotations already declare readOnly, idempotent, closed-world and non-destructive, so the safety profile is covered. The description adds genuinely new behavioral detail: the payload is the contents of the root AGENTS.md file and the result is null when no prompt is set — important since there is no output schema.

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?

Three compact sentences with zero padding: the purpose and the pre-work instruction are front-loaded, followed by the return-value contract. Every clause carries information an agent needs.

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 single-parameter read with no output schema, the description covers both side of the contract (what content comes back, and the null case). It does not mention error or permission conditions (e.g., board not found / not a member), a minor remaining gap.

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?

Only one parameter, and the schema documents board_id at 100% coverage ('Board ID to read the prompt for'), so the baseline is 3. The description adds no syntax, format, or validity details beyond that.

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 (fetch) and a precisely scoped resource (the board-level agent prompt / root AGENTS.md file), so the agent knows exactly what comes back. It does not explicitly name the sibling it differs from (e.g., list_board_files or update_board_file), which keeps it short of a 5.

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?

'Read this into your context before working a board' is an explicit when-to-use directive, which is more than most tool descriptions provide. There are no when-not conditions or named alternatives (e.g., use list_board_files to enumerate all files instead).

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