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

With no annotations provided, the description carries the full behavioral burden. It does add one useful transparency point: setting agent_card_url triggers an immediate fetch and verification. However, it does not disclose whether updates are partial or replace-all, whether authorization via api_key is needed, or what happens on success or failure.

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 description is a single, front-loaded sentence that names the action and all relevant fields, then adds the most important behavioral caveat at the end. There is no filler, redundancy, or repetition of schema constraints.

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?

The tool has six parameters, no annotations, and no output schema, so the description needs to do more. It covers the update surface and card verification, but omits usage conditions, the role of api_key, semantics of capabilities, and response behavior. An agent would still have to infer several calling conventions.

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?

The description lists the five updatable fields and implicitly distinguishes them from the api_key authentication parameter, which is helpful given the low schema description coverage of 17%. It adds specific behavior for agent_card_url but offers no added meaning for capabilities, name, or description beyond their names.

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 uses a specific verb, 'Update', and precisely enumerates the resources being modified: name, description, capabilities, webhook_url, and agent_card_url. This clearly differentiates it from siblings like register_agent, delete_agent, and get_agent, and even adds a distinct behavioral detail about the agent card being fetched and verified.

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?

The intended use is implied: use this tool to modify fields on your own agent. However, there is no explicit guidance about when to use it versus alternatives, and no mention of prerequisites or exclusions. The verb 'Update' provides some context but does not fully disambiguate against update_intent or register_agent-related workflows.

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