firestarter_spend_cap

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description's 'Read-only' statement reinforces rather than adds novel safety info. However, it adds valuable context beyond annotations by clarifying the exact data read (spend cap and alert threshold) and the operational significance (SPEND_CAP_EXCEEDED rejection). This enriches behavioral understanding without contradicting 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?

The description is two sentences, completely front-loaded with the primary purpose, and includes a succinct pointer to the sibling tool. Every word earns its place with no redundancy or filler.

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 zero-parameter, read-only tool with strong annotations and no output schema, the description fully covers the tool's behavior and context. It explains what is read, defines key terms, and directs to the appropriate tool for mutations. The inclusion of the SPEND_CAP_EXCEEDED scenario adds operational completeness.

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 has zero parameters, so the schema has nothing to explain. The description doesn't need to detail parameters; instead, it describes what the read operation returns (spend cap and threshold), which provides semantic clarity. Per rubric, a baseline of 4 is appropriate for tools with no parameters, and no deduction is warranted.

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 clearly states the tool's function: 'Read the buyer's monthly spend cap - the safety limit on total monthly spend - and the alert threshold at which a warning fires.' This specific verb+resource combination distinguishes it from the sibling tool firestarter_set_spend_cap, which is explicitly mentioned for modifications.

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 provides explicit usage guidance: it identifies the tool as read-only and directs users to firestarter_set_spend_cap for any modifications, including a specific scenario ('after a purchase is rejected with SPEND_CAP_EXCEEDED'). This clearly explains when to use this tool versus the alternative.

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