canvas_edit_image

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

Description details all actions and includes an important note about opening output in Preview. Annotations indicate mutation but no contradiction. Could mention side effects or error handling.

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?

Well-organized with clear sections, bulleted actions, and a concrete example. No wasted words, front-loaded purpose.

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?

Covers purpose, usage, actions, and a follow-up step. Output schema exists so return values are covered. Could include prerequisites or error states.

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 has per-parameter descriptions, but description adds value by listing actions with context (e.g., prompt required for edit) and providing an example.

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 modifies/enhances/transforms existing images, lists four specific actions, and distinguishes from siblings like canvas_create_image and canvas_render_layout.

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?

Provides explicit 'Use when' and 'Do not use when' sections with named alternatives (canvas_create_image, canvas_render_layout).

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