Render an email

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

No annotations are provided, so the description must carry full behavioral disclosure. It mentions warnings (non-fatal repairs) and previewUrl, which gives insight into side effects. It does not detail auth requirements, rate limits, or error handling, but the key behavioral traits are addressed.

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 a single sentence that front-loads the core purpose ('Render emailmd markdown into email-safe HTML') and then enumerates return fields. It is concise but could be more structured (e.g., separate sentences for purpose and outputs).

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 no output schema or annotations, the description lists all return fields and clarifies the nature of warnings. It lacks explicit error handling or failure modes, but for a render tool with 3 parameters, it provides sufficient context for an agent to 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?

Schema coverage is 100%, so the baseline is 3. The description adds no additional meaning to the parameters beyond what is in the schema; it only describes return values. The parameter details (minify, markdown, partials) are already well-documented in 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 'emailmd' markdown into email-safe HTML, and lists the specific return fields (html, text, meta, warnings, htmlBytes, previewUrl). This verb+resource pair is distinct from sibling tools 'lint' and 'read_docs' which serve different purposes.

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 implies use for converting markdown to email HTML, and sibling tools provide context for when not to use it (e.g., use 'lint' for validation, 'read_docs' for docs). However, it does not explicitly state when to prefer this tool over alternatives or mention any prerequisites.

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