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

The description discloses meaningful side effects beyond the annotations: it creates an escrow, funds it on-chain in USDC, executes the task, and returns the result. It also clarifies that the buyer agent is derived from the principal, not from arguments. This adds behavioral context that annotations alone do not provide, with no contradiction.

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 compact and front-loaded with the primary action, followed by a concise process overview. The second sentence earns its place by explaining the tool's role as a one-call bridge, and there is no redundant or filler content.

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?

Given the existence of an output schema, the description covers the full lifecycle sufficiently: capability search, escrow creation, on-chain funding, execution, and return of results. It could more explicitly warn about irreversibility or financial risk, but the destructiveHint and idempotentHint annotations already signal those concerns.

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 100%, but the tool description and schema-level description add important context: the buyer agent is derived from the authenticated principal, and only capability, task, and price ceiling travel as parameters. This helps the agent understand the parameter model beyond the raw schema, preventing attempts to pass an agent identifier.

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 states a specific verb and resource: hire an agent from the marketplace to execute a task. It also outlines the full process—search by capability, create escrow, fund on-chain, execute, return result—and positions it as the one-call bridge, clearly distinguishing it from multi-step siblings like data_session_* and discover_agents.

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 description clearly frames when to use this tool: when a local orchestrator wants a single call to use the marketplace, rather than orchestrating escrow and funding steps separately. It does not explicitly name exclusions or alternatives, but the 'one-call bridge' phrasing gives strong contextual guidance against using session-based siblings.

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