canvas_edit

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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description goes further by disclosing the blast radius of specific operations — notably that replace without section_id overwrites the entire canvas — which is exactly the kind of consequence detail annotations cannot express.

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 'Apply one edit' then packs operation semantics into two dense sentences with no filler. The run-on operation list is information-rich but slightly hard to scan as a single block.

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 4-parameter mutation tool with no output schema, the description covers the operation vocabulary, the conditional requirements on section_id, and the destructive scope of a full-canvas replace — enough for an agent to invoke it correctly on the first try.

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 carry parameter meaning, and it largely does: it enumerates all seven operation values, explains when section_id is mandatory, and clarifies that markdown_content doubles as the new title for rename. It leaves insert_at_start/insert_at_end's payload requirement unstated, and canvas_id undefined.

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 ('apply one edit') and enumerates the exact operation set, so an agent immediately knows this is the single mutation entry point for canvas content. The resource is only implied through the tool name rather than the description text, and no sibling is contrasted, keeping it just short of a 5.

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 per-operation conditions: insert_before/insert_after/delete require section_id, replace without section_id replaces the whole canvas, rename repurposes markdown_content. It also routes the agent to canvas_find_sections to obtain section_id. It stops short of stating when to reach for canvas_edit versus canvas_create.

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