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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and scope are covered. The description adds valuable behavioral context that annotations cannot: it enumerates the return payload (official summary, price, run link), which matters because there is no output schema. It does not mention pagination or how the limit interacts with results, but overall it adds real value beyond the structured fields.

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 sentences, zero waste. The core action is front-loaded, the examples are compact, and the return payload is stated in a single trailing clause. Nothing could be cut without losing 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?

With no output schema, the description usefully covers what comes back, and the annotations handle the safety profile. The main remaining gap is that a search tool with a limit parameter says nothing about result volume or ranking, and sibling routing is unaddressed, but for a read-only discovery tool this is close to complete.

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 50%: query is documented in the schema ('What the user needs done. Empty returns all agents.') but limit is bare. The description adds no parameter-level detail (no guidance on sensible limit values or query phrasing beyond examples), so it neither compensates for the gap nor falls below the baseline for a partially documented schema.

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 (Search) and resource (Finch marketplace of third-party AI agents) scoped by task, with five concrete example queries that make the search space tangible. It does not explicitly contrast itself with siblings like get_finch_agent or how_to_call_finch_agents, so an agent must infer the distinction, but the purpose itself is unambiguous.

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 phrase 'by task' plus the example queries implies the appropriate use case (discovery when you have a need expressed in natural language), and 'Empty returns all agents' hints at the browse case. However, there is no explicit guidance on when to use this versus get_finch_agent (direct lookup) or how_to_call_finch_agents, leaving the routing decision to inference.

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