render_diagram

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

The description adds useful context beyond annotations: it reveals that when format is 'png', the tool saves to a temp file and returns the path, and describes return formats (SVG text vs base64 PNG). This complements the readOnlyHint and idempotentHint annotations without contradicting them.

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, with four short sentences that front-load the purpose and then add return details and a syntax pointer. No information is redundant or wasted.

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?

The tool has 4 parameters and a clear return type, and the description covers output formats, side effects, and a reference to the syntax guide. It is sufficiently complete for an agent to invoke it correctly, given the schema and annotations.

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%, but the description reinforces the dgmo parameter with the 'Sales red' example and adds the side effect of the format parameter for PNG. This adds value beyond the schema's 'Output format' description.

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 DGMO markup to SVG or PNG, with a specific verb and resource. It also distinguishes itself from get_language_reference by directing syntax questions there, but does not explicitly differentiate from the similar preview_diagram sibling.

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 guidance to call get_language_reference for DGMO syntax, implying this tool is for rendering. However, it doesn't offer exclusion criteria for when not to use this tool versus preview_diagram or other siblings.

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