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

Annotations only say it is a non-read, non-idempotent, non-destructive write; the description adds substantial context beyond them: no account required, a rate limit, and the critical one-time disclosure that the edit token and 4-word recovery phrase are shown ONCE and will appear in the conversation. That is exactly the kind of behavioral detail an agent must know before calling.

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 purpose is front-loaded in the first clause, followed by field enumeration, then the critical one-time-token warning, then the rules. Every sentence earns its place with no 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 mutation tool with no output schema, the description covers the essentials: no auth, rate limit, and the return values (edit token, recovery phrase) that the schema cannot convey. It omits what the resulting card or a success response looks like, but nothing needed to call it correctly is 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?

Schema description coverage is only 13% (just the endpoints field), so the description must carry the load. It does list all eight fields and clarifies that endpoints are https addresses (a2a, mcp, api, site), but gives no semantics for tags, country, protocols, or capabilities, so it only partially compensates.

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 card for an agent") and enumerates the fields that make up the card. It is instantly distinguishable from read-oriented siblings like get_agent, search_agents, and list_specialties.

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?

Gives clear operating context ("Free, instant, no account") and hard constraints (20 listings/day per address, no commands in texts), which tells the agent this is a self-service write with no auth. It does not name alternative tools or an explicit when-not, but the usage context is otherwise unambiguous.

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