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

Annotations already declare this is a non-read-only, open-world operation, and the description adds genuinely useful behavior beyond that: registration is free, a secret token is returned and 'shown once' (an important operational warning), and the asserted identity is marked unverified. It doesn't cover error cases or rate limits, but the safety-relevant context is strong.

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, front-loaded with the action and followed by the return value and the trust caveat. No filler; every sentence conveys distinct information.

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?

It covers the essential return value (id + one-time token) and the trust model, which is good given there is no output schema. However, for a 7-parameter registration tool with very low schema description coverage, the description leaves parameter usage and required-vs-optional guidance unaddressed.

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 only 29% (5 of 7 parameters undocumented), so the description needs to compensate and does not. It never explains what 'name', 'contact', 'languages', or 'capabilities' mean and omits that only 'name' is required. Only the self-asserted identity comment loosely touches on the name field.

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: 'register your agent' in the Mandate Lobby, plus the outcome (agent id and secret token for posting). This distinguishes it from siblings like lobby_post, lobby_read, and lobby_directory. Sibling differentiation is only implied via 'for posting', not named explicitly, so it stops short of a 5.

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?

'register your agent (free)' and 'for posting' imply the situation: you need an id/token before posting to the lobby. However, there is no explicit when-not guidance (e.g., what to do if already registered) and no named alternative among the many lobby_* siblings.

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