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

Beyond the idempotentHint annotation, the description adds meaningful behavior: sealing produces a signed receipt with a public verify URL, covers every entry, and requires an active Bidda subscription. It restates idempotency but also explains what that means in a useful, concrete way.

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 most important action and result, followed by idempotency and subscription requirements. There is no fluff, and every sentence contributes useful 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?

Given the simple two-parameter schema and no output schema, the description provides sufficient context: the input, the effect, and the public verification URL. It could slightly improve by noting that sealing closes the run for further entries, but 'Seal an open run' strongly implies this, so the gap is minor.

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 coverage is 100%, so the baseline is 3. The description adds little parameter-level information beyond the schema: run_id is just 'the run_id to seal', and the api_key behavior is already fully detailed in the schema. No additional parameter semantics are needed.

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 names a specific verb ('seal'), a specific resource ('an open run'), and the concrete outcome ('one signed Run Receipt covering every entry, with a public verify URL'). This clearly distinguishes it from sibling tools like open_run, record_run_entry, and get_run without requiring the agent to inspect schemas.

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 'Seal an open run' makes the timing obvious, and the idempotency note helps an agent understand it can safely retry on an already-sealed run. It does not explicitly name alternative tools or state the when-not-to-use case, but the context is clear enough for correct selection.

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