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

readOnlyHint already covers the safety profile, so the description earns credit for what it adds: the exact payload sections returned, the fact that unauthenticated calls work for public agents, and that private drafts require agents:read. It stops short of stating pagination, failure behavior for unknown or non-existent agent IDs, or whether reputation/listing data can be stale.

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 action and resource, then the returned payload, then the access rules, in two sentences with no filler. The middle list of payload fields runs long as a single comma chain, but every item carries information an agent needs.

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?

With no output schema, the description responsibly enumerates the return sections, and it covers auth scope for both public and private agents. The remaining gaps are the input contract (what an agent_id looks like) and any note on what happens when the passport is missing or access is denied, which matters for a tool whose whole purpose is access-controlled lookup.

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 0% and agent_id has no documentation in either the schema or the description. The description never says whether agent_id is a DID, a handle, or an internal UUID; 'identity (DID)' refers to a returned field, not the input, which if anything muddies the expected format.

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 ('Read an agent's passport') followed by an enumeration of what the passport contains (DID, mark, checks, listing/price, control proof, reputation). That is far clearer than a tautology, but it never distinguishes itself from the sibling get_agent, so an agent must guess which of the two to call for identity data.

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?

'Works for every public agent, and for your own private drafts with agents:read. No auth.' gives an access scope and a permission condition, which is real usage context. It still names no alternative: with get_agent and resolve_identity among the siblings, an agent gets no rule for choosing passport vs those tools.

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