firestarter_set_spend_cap

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

Annotations already communicate that this is not read-only and is potentially destructive, but the description adds genuinely useful behavior: disable:true removes the cap entirely, and a purchase previously rejected with SPEND_CAP_EXCEEDED will succeed after the cap is raised and the purchase retried. This is meaningful operational context beyond 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?

The main action is front-loaded, and every sentence adds distinct value: intent paraphrases, the SPEND_CAP_EXCEEDED workflow, the disable path, and the read-only sibling. It is thorough without being padded, and the detail is justified by ambiguity in natural-language requests.

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 three-parameter, optional output-less mutation tool, the description is very complete: action variants, retry semantics, disable behavior, and the read sibling are all present. It loses one point for not addressing the combination of disable:true together with spend_cap_dollars, and for leaving alert_threshold_pct to be discovered solely through the schema.

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%, with each parameter already well documented. The description adds only a natural-language example ($100) and tells the agent use disable:true to remove the cap, but it does not materially expand the parameter semantics beyond what the schema already provides.

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 is action-first: 'Raise, lower, set, or remove the buyer's monthly spend cap' and gives concrete user phrase examples. It also explicitly contrasts with the sibling firestarter_spend_cap by saying that tool is for reading the current value, so the boundaries are unambiguous.

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?

It explicitly states when to use this tool: whenever the user wants to increase, raise, set, lower, or change the cap. It also defines the SPEND_CAP_EXCEEDED flow, where raising the cap here lets a rejected purchase go through on retry, and tells the agent to use firestarter_spend_cap for read-only lookups.

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