Quote a revision of a run

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

Annotations already declare readOnlyHint=true, but the description goes well beyond them: it discloses billing semantics (delivered revisions charged the quoted total, failed ones charged nothing even after paid work), the editing_disabled response while paid edits are closed, and the exact output fields (summary, billing.total_credits). That is rich behavioral context an annotation cannot carry.

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 key value proposition ('WITHOUT spending credits') is front-loaded in the first clause, and each subsequent sentence adds distinct information: call shape, ordering requirement, billing outcome, and the editing_disabled case. No sentence is redundant with the schema or annotations.

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 complex nested-input tool with no output schema, the description covers how to invoke it, the ordering with revise_run, the billing outcome, and the fields returned. Nothing an agent needs to call it correctly and report the price to a user 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?

Schema coverage is 100%, so the baseline is 3. The description adds a real constraint the schema does not enforce: 'exactly one of changes or document' (the schema only requires run_id and never expresses the mutual exclusion). It also names the return fields, but does not explain the modes or document structure further, so it sits just above baseline rather than at the top.

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 and resource ('Price a revision of a run') and immediately scopes it as the no-credit quoting step, which distinguishes it from revise_run and from the sibling quote_faceless/quote_ugc/quote_actor tools. An agent can tell what this does and what it does not do without opening the 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?

Explicit ordering rule: 'Always call this first and show the user the price before revise_run.' It names the alternative (revise_run) and the condition that selects it, leaving nothing to inference. This is exactly the when-to-use/when-to-use-something-else guidance the dimension asks for.

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