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

Beyond the single destructiveHint annotation, the description discloses two important traits: Stiply fetches each PDF from file_urls server-side, and signers are emailed immediately and simultaneously. The immediate-email disclosure is exactly the kind of irreversible side-effect context an agent needs. It omits auth/permission requirements and what is returned after sending.

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 tight sentences with the operation class ('WRITE') front-loaded, followed by the key side-effect, the safety caution, and the endpoint. Zero filler; every sentence earns its place.

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 an 8-parameter mutation tool with no output schema, the description covers purpose, side effects, and a usage caution well. The main remaining gap is what the call returns (e.g. a sign request id needed for stiply_get_sign_request_progress), which an agent would want to know.

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 description coverage is 88%, so the schema already explains title, signers, fields, term, and the rest. The description only adds that file_urls entries are downloaded by Stiply, which slightly clarifies that parameter but adds little beyond the schema's own 'Public https URLs' description. 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 and resource ('create a sign request and SEND it') plus the exact API endpoint, which unambiguously separates it from read tools like stiply_get_sign_request and stiply_list_sign_requests. It stops short of naming any sibling to contrast with, so it lands at clear-but-not-differentiating.

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?

'Confirm the signers with the user first' gives a concrete pre-condition for invoking the tool, which is more than most definitions offer. It does not name alternatives (e.g. extend_term or cancel) or state when not to use it, keeping it below a 5.

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