draw_text

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

Annotations already declare the safety profile (readOnly=false, destructive=false, openWorld=true, idempotent=false), so the bar is lower. The description adds real behavioral detail (fonts weld into one stroke per word; speed controls pen-down step size), but says nothing about physical-plotter side effects, connection/auth requirements, or what happens to prior output.

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?

Front-loads the core action, then layers font advice, the scene alternative, and speed semantics. Dense but ordered; a couple of clauses (e.g. the G94 aside) are jargon-heavy for the value they add.

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 an 8-parameter tool with 0% schema coverage and no output schema, the description covers purpose, fonts, an alternative, and speed, but leaves order semantics and the auto-fit behavior of null w/h unexplained. Adequate but with clear gaps given the complexity.

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 clarifies the box coordinates (x,y,w,h in mm) and the speed parameter ('G94 S, max step size for pen-down moves, 1..30'), and names good font values, but leaves `order` (default 'human') and the null w/h behavior entirely undocumented.

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?

States a specific verb and resource ('Write text with a single-stroke Hershey font') plus the operating constraint ('fitted into box (x,y,w,h) mm'). It also names the sibling alternatives (list_fonts, draw_scene), so an agent can distinguish this from preview_text/draw_scene without opening any schema.

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?

Gives concrete guidance: prefer handwriting faces for specific looks, and 'For multi-line or MULTI-FONT text prefer a scene: draw_scene' names the alternative and the condition that selects it. It stops short of explicit when-not-to-use exclusions, but the routing advice is actionable.

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