buy_credit

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

No annotations are provided, so the description carries full burden. It fully discloses behavioral traits: credit is face-value, per-provider, non-refundable at expiry, and is consumed by call_api. This covers the key behavioral aspects an agent needs to avoid mistakes.

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 somewhat lengthy but efficient. It front-loads the main action and then adds necessary context. Every sentence contributes meaning, though it could be slightly tightened without losing clarity.

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 there is no output schema, the description adequately explains what happens upon purchase and how credit is used. It covers the lifecycle enough for an agent to use the tool correctly, though it omits details like balance checking or expiry specifics, which are minor gaps.

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 detailed parameter descriptions, so baseline is 3. The description adds value by explaining the relationship between parameters (e.g., credit_sats is face value, path is any endpoint for verification) and the overall workflow, justifying a 4.

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 verb 'Buy prepaid CREDIT' and specifies the resource 'bolthub provider'. It distinguishes the tool from siblings like call_api by explaining that credit is drawn when calling APIs, and contrasts with per-endpoint payment. The purpose is 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?

The description explicitly says 'Use this when you'll call SEVERAL of one provider's endpoints' and provides a rule of thumb: sum costs and buy that much credit. It also clarifies that credit is per-provider and non-transferable, effectively advising against using it for single calls or multiple providers.

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