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

Adds behavior beyond annotations: 'Each call is a new report' explains the non-idempotentHint=false semantics, and 'A token that acts for no person is refused' discloses an auth failure mode. It does not say what happens to reports afterwards or what the call returns, which with no output schema is a minor gap.

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?

Front-loaded with the core purpose, then preconditions, then the negative constraint and auth caveat. Every sentence carries information; only 'Each call is a new report' is close to restating the non-idempotent annotation.

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 two-parameter write tool with no output schema and full annotation coverage, the description supplies the trigger, the sibling that gates it, the privacy constraint, the anti-guessing rule and the refusal condition. Nothing an agent needs in order to invoke 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 already 100%, so baseline is 3; the description adds value by mapping example situations ('no repository yet', 'no wish to set up model keys or credits', 'no time now') onto the reason enum values, and by framing the detail parameter as the person's own words. It does not add format guidance beyond the schema.

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 ('Record why...will not finish setting up') on a specific resource (setup blocker reason, in the person's own words), with concrete examples of what qualifies. It is clearly distinguishable from read-oriented siblings like get_setup_progress and mark_setup_step.

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?

Explicit preconditions: 'Call it only after the person said why', 'Ask them when get_setup_progress shows setup is not done', plus a negative rule 'Do not guess a reason'. It names the sibling that triggers it and the condition that selects this tool.

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