blend-ai

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

With no annotations provided, the description carries full burden for behavioral disclosure. It mentions the tool can output to a file or return base64 data, but doesn't address important behavioral aspects like whether this is a read-only operation, if it requires specific viewport state, what happens if the filepath is invalid, or any performance/rate limit considerations. For a tool with no annotations, this is insufficient.

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 efficiently structured with a clear purpose statement followed by organized sections for Args and Returns. Every sentence adds value, with no redundant information. The formatting makes it easy to parse quickly.

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 that there's an output schema (which handles return value documentation), no annotations, and 3 parameters with good description coverage, the description is minimally adequate. However, for a tool that interacts with viewport rendering, it lacks context about viewport state requirements, performance implications, or error conditions that would help an agent use 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?

With 0% schema description coverage, the description fully compensates by explaining all three parameters: filepath (optional, absolute path, base64 fallback), width (render width in pixels, default 1920), and height (render height in pixels, default 1080). It adds meaningful context beyond the bare schema, though it doesn't specify constraints like minimum/maximum values.

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 tool's purpose: 'Render the viewport to a file or return as base64.' It specifies the action (render) and resource (viewport), but doesn't explicitly differentiate from the sibling tool 'get_viewport_screenshot' which appears to serve a similar function. The purpose is clear but sibling differentiation is missing.

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 provides no guidance on when to use this tool versus alternatives like 'get_viewport_screenshot' or 'render_image'. It explains what the tool does but offers no context about appropriate use cases, prerequisites, or comparisons with sibling tools.

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