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

Annotations cover the safety profile (readOnly, idempotent, non-destructive), but the description adds genuinely useful behavior beyond them: no bearer token is required, the model is not executed, and only execution consumes prepaid run units. That billing/auth context is not derivable from the annotations.

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 tightly packed sentences with zero waste. The return contents are front-loaded, followed by the cost/auth constraints that matter for invocation.

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 no-param metadata tool with no output schema, the description enumerates the returned fields and the invocation constraints, which is close to sufficient. Minor gaps remain around the format/currency of the listed price and endpoint shape, but nothing essential 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?

The tool takes zero parameters, so the schema imposes no semantic burden and the baseline is 4. There is no argument syntax for the description to clarify.

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 ('Returns') plus the exact resource set: identity, per-task price, MCP endpoint, and access URL. This clearly separates it from the execution siblings (create_run, get_run_result), which an agent can distinguish without opening a schema.

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?

Establishes clear context that this is a metadata call that does not run the model and needs no bearer token, so an agent knows to use it for discovery/preflight rather than execution. It stops short of explicitly naming the alternative tools (e.g. agentfarm_create_run) for actually running the agent.

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