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

Beyond the annotations (not destructive, open world), the description discloses two real behavioral traits: the operation is charged per image, and the result is rendered inline while also receiving its own asset_id (implying a new asset rather than in-place mutation, consistent with destructiveHint=false). It does not cover failure modes or rate limits, but for a one-parameter image transform this is solid added value.

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?

Three short sentences, front-loaded with the action and output, then use cases, then cost and return behavior. Every sentence carries distinct information with 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 compensates by explaining what comes back – an inline result plus an asset_id – and warns about per-image cost. Combined with a single well-documented parameter, an agent has everything needed to call it correctly.

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?

There is a single parameter with 100% schema description coverage, so the schema already explains that asset_id is an asset from a previous result or upload. The description adds nothing about parameter format or sourcing beyond that, so the baseline of 3 applies.

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 (remove) and resource (background of an image) plus the precise output form (subject on transparency, PNG). No sibling tool does background removal, so an agent can distinguish it from upscale_image, vectorize_image, and animate_image without further reading.

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 gives clear situational context – product shots, logos, stickers, portraits – which tells the agent when this tool is the right fit. It stops short of naming exclusions or alternative tools for cases where background removal is the wrong choice.

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