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

Beyond the annotations (readOnlyHint false, destructiveHint true, openWorldHint true), the description discloses rate limiting (max 2 per 60 minutes, returns 429), the 403 response on wrong document status, and the meaning of signeeDetails[].reminders.reminderCooldown. This is detailed operational behavior that annotations do not provide.

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?

The description is information-dense but every sentence earns its place: main action, mandatory pre-call, two precise conditions, user-confirmation requirement, rate limit, and cooldown handling. It is structured with numbered conditions and code identifiers for clarity, and it front-loads the most important operational step ('Always call get_document first') immediately after the main action.

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 write tool with two parameters and no output schema, the description covers all essential context: preconditions, parameter sourcing, failure modes (403, 429), cooldown semantics, and user-interaction expectations. Nothing an agent needs to call this tool correctly appears to be 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?

The input schema already covers both parameters with 100% description coverage, so the baseline is 3. The description adds substantial meaning beyond the schema by explaining that signeeIds must be filtered to only awaiting_signature signees and that documentId must reference a document in awaiting_signatures status. This goes beyond the schema's 'Unique identifier of the document' and 'Signee IDs to remind', earning a 4 rather than a 3.

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?

The description states a specific verb ('Send'), a resource ('signing reminder to one or more signees'), and the condition 'who have not yet signed.' It clearly distinguishes this tool from siblings like send_draft and update_signee, making its unique role obvious.

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?

It explicitly instructs 'Always call get_document first' and states the two preconditions (document status must be awaiting_signatures, signees must have signatureStatus awaiting_signature). It also provides a rule for user interaction ('Show who will be reminded and ask for confirmation') and a retry guideline with cooldown checking, leaving no ambiguity about when and how to invoke the tool.

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