Remove background from image (Recraft + fal.ai BiRefNet v2 fallback)

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

The description discloses costs (~5 credits per image), provider fallback behavior (Recraft to fal.ai BiRefNet v2), and failure semantics ('single-image calls never silently fail'). It also addresses edge cases like transparent-PNG inputs, all beyond the sparse annotations. No contradictions with 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 compact and front-loaded with the primary action, followed by key context (cost, fallback, limitations). Every sentence provides value without redundancy or verbose explanation.

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?

Despite having no output schema, the description specifies the return format (PNG with transparent alpha). It covers costs, provider fallback, ideal use cases, and a limitation, making it complete for a single-parameter tool.

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 schema already fully describes the only parameter with 'Public URL of the source image' and format uri. The description repeats 'Pass a public `imageUrl`' without adding new semantic detail, so it meets the baseline for high schema coverage but does not improve on it.

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 opens with 'Strips the background from an image, returning a PNG with transparent alpha,' clearly stating the verb, resource, and outcome. It distinguishes itself from siblings like aetherwave_remove_background_video by explicitly targeting images and noting the fallback to BiRefNet v2.

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 provides explicit use cases ('product shots, character cutouts, logo isolation...') and a clear when-not-to-use ('transparent-PNG inputs have no foreground to segment'). However, it does not explicitly name an alternative tool for video or editing, relying on sibling names rather than direct comparison.

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