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

No annotations are provided, so the description carries the behavioral burden. It does disclose return behavior (match reasons, provenance fields), which is useful, but says nothing about read-only semantics, result limits (the schema caps limit at 25), pagination behavior, or auth requirements.

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?

Two tight sentences, front-loaded with the usage trigger before the mechanics. Dense but no filler, though the return-value sentence could be deferred since there is no output schema to lean on.

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 seven-parameter search tool with no annotations and no output schema, the description covers the trigger and the return shape but omits pagination semantics, filter interaction (AND vs OR), and any example values. Adequate but with clear gaps.

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%, so the description must compensate. It maps prose filters to four of the seven parameters (skill, protocol, signatureStatus, source) but adds no accepted values, formats, or matching semantics, and leaves query, page, and limit entirely unexplained.

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?

Names a specific verb (searches) and resource (A2A agents) and enumerates the filter dimensions (capability, protocol, signature, source), which distinguishes it from the sibling search_servers. It stops short of explicitly contrasting with get_agent or inspect_agent_passport, so it is clear but not fully sibling-differentiated.

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?

"Use when you need another agent with a specific capability or protocol" gives an explicit trigger condition rather than leaving usage to inference. There is no when-not guidance and no named alternative (e.g., get_agent for a known agent), but the context is clear.

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