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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context the annotations cannot convey: rendering varies by host (apps-capable hosts get a reminder button, other clients get plain text). It does not describe pagination or error behavior, but for a single-document read that 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?

Three tight sentences: purpose first, host-dependent rendering second, prerequisite last. Nothing is repeated from the schema or annotations and no sentence is padding.

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 read-only, idempotent, single-parameter tool with no output schema, the description covers what is shown, how it renders per host, and how to obtain the ID — everything needed to call it correctly. The one omission is disambiguation from assinafy_get_document, which matters given the sibling set.

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?

There is one parameter with 100% schema description coverage, so the schema already documents document_id. The description adds only a light provenance hint ('one known document' resolved via assinafy_list_documents), not format or constraint details, so the baseline 3 for high-coverage schemas is appropriate.

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 names a specific verb and resource ('Show a status card for one known document') and enumerates exactly what the card contains: status, signers completed, signers pending, expiry. That is far more informative than a tautology. It loses a point because it never distinguishes itself from the near-identical sibling assinafy_get_document, which an agent would plausibly confuse with this tool.

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 gives explicit workflow guidance: 'Resolve the document with assinafy_list_documents first,' which tells the agent how to obtain the required document_id. What it does not provide is any when-to-use/when-not guidance relative to assinafy_get_document or the other read siblings, so the routing decision is left partly to inference.

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