Remove background

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

Goes well beyond the annotations: it discloses a concrete 0.2 USDC real-money charge on Base via x402, that spending limits are enforced, that allow_repeat silently returns a prior result without charging, and that max_price_usdc can refuse the purchase. These are exactly the cost/auth side effects an agent needs before firing a non-readonly, non-idempotent call.

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?

Dense but front-loaded: purpose, then cost/payment, then input constraints, then output. Every clause carries information (cost, formats, size caps, exclusivity) and there is no 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?

With no output schema, the description still specifies the return (image/png as a download link, plus a file when save_to is used) and covers payment, constraints, and dedupe behavior. An agent has everything needed to call this safely and interpret the result.

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, but the description adds a constraint the schema does not encode: 'Give exactly one of image_url or image_path' (the schema shows zero required params and no oneOf). That mutual-exclusivity rule and the PNG/link vs save_to output distinction are genuine added meaning.

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 ('Removes the background from one photo') plus the exact result ('subject on a transparent background as a PNG, at the photo's own size'). It is trivially distinguishable from siblings like optimize_image or image_palette, which transform rather than cut out subjects.

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?

Gives real operating context: cost per call, that payment is checked against spending limits, and that exactly one of image_url or image_path must be supplied. It does not, however, name an alternative tool or an explicit 'don't use this when...' condition.

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