render_proof

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

Annotations provide no meaningful safety hints, so the description carries the burden. It discloses useful behavior beyond the name: missing glyphs become explicit placeholders, revisions can be compared, and all glyphs share one scale. This adds practical expectations without contradicting 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?

Two short sentences deliver the core capability, key limits, a behavioral guarantee, and a routing alternative. There is no filler or repetition.

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?

For a 12-parameter tool with 0% schema description coverage, the description only partially covers the invocation surface. The top-level purpose and the most important differentiation are clear, and an output schema exists, but several parameters still lack guidance. This is adequate but not complete.

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 0%, so the description must compensate. It captures the central parameter meanings: glyph count ('up to 32 glyphs'), unified scaling ('one common scale'), and revision comparison. However, it leaves several parameters unspecified (detail, guides, points, columns, master_id, image_mode, cell dimensions), relying on schema names and enums.

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 states a specific verb ('Render'), a bounded resource ('up to 32 glyphs'), and a distinguishing mode ('one common scale, optionally comparing revisions'). It also explicitly separates itself from render_text for shaped words, which helps distinguish it from a close 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 clearly says to use render_text for shaped words instead, an explicit when-not with an alternative. However, it does not explicitly mention render_glyph for single-glyph rendering or other alternatives, so some usage context is left implied.

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