store_doctor

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

With no annotations the description carries the full burden, and it does useful work: it discloses that the check makes real API calls (so it is a live network operation, not a cached/offline lookup) and that it is a read-only diagnostic returning per-store auth status. It does not disclose latency, rate-limit exposure, or whether the live calls can trigger side effects such as 2FA prompts, which would complete the picture.

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 short sentences: capability first, then the trigger condition, then the return shape. No filler, nothing repeated from schema or annotations.

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?

An output schema exists, so the description does not need to enumerate return fields, yet it still summarizes the useful signal ('whether the credential authenticates and what is missing'). For a zero-parameter diagnostic this is complete.

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?

The tool takes no parameters, so the baseline expectation is that nothing needs explaining. The description confirms it acts on 'both stores' implicitly and requires no input, which matches the empty 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?

Specific verb+resource: 'Check the credentials for both stores with real API calls', scoped to both Apple and Play credential checks. No sibling tool covers the same ground (store_audit_identity audits identity, not credential validity), so an agent can select it without schema inspection.

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?

'Use this before investigating any authentication error' gives an explicit trigger condition and a clear ordering relative to other diagnostics. It stops short of naming a when-not condition or an alternative tool, so it is clear context rather than full routing guidance.

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