Render Image

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

No annotations are provided, so the description carries the full burden. It mentions the return value (signed download URL for PNG), but does not disclose other behavioral aspects such as rate limits, authentication requirements, or whether the operation is idempotent. Adequate but not exhaustive.

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 two sentences long, front-loaded with the core purpose, and contains no unnecessary information. Every sentence is valuable and direct.

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 is no output schema, the description adequately covers the return type (signed download URL). It also mentions the html size limit (512 KB) indirectly via schema. Could be more complete about the URL format or expiration, but overall sufficient for a tool with three parameters.

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 description coverage is 100%, and the description adds value by explaining the relationship between template_id and html (alternatives) and referencing list_templates. The data parameter is described as Handlebars data object, which adds context beyond the schema.

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 renders a PNG image using the DocJet API, with specific use-case examples (OG/social card). It distinguishes itself from sibling tools by specifying PNG output vs list_templates and render_pdf.

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 explains the two options for input (template_id or raw html) and mentions using list_templates to discover template IDs. It provides clear guidance on what to provide, but could be improved by explicitly stating when not to use this tool (e.g., for PDF rendering).

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