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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds real value beyond that by disclosing what the operation returns ('what to say instead and why'), which matters because there is no output schema, and by pointing to which inputs select which target. It says nothing about rate limits, empty-brand behavior, or result size limits.

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?

Three short sentences, no filler, with the core purpose front-loaded before the input options and the usage nudge. Every sentence carries distinct information.

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?

Read-only safety comes from annotations, source selection and return content come from the description, and all five parameters are documented in the schema; with no output schema, the description's note about returning the offending words plus replacements and rationale fills the remaining gap. An agent has enough to invoke it correctly.

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%, so the baseline is 3, but the description adds a relationship the schema cannot express: that text, boardId, and docId are alternative ways to supply the content to check (the schema merely lists all five as optional with no exclusivity). It does not clarify kitId or workspace, which the schema already documents.

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?

Specific verb+resource: 'Finds words the brand says to avoid in a piece of writing', and it clarifies the return payload (what to say instead and why). This is clearly distinguishable from siblings like napkin_brand_get, napkin_brand_list, or napkin_brand_apply.

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 a concrete usage occasion: 'Run it on your own drafts before handing them back', which tells the agent when to reach for this tool. It does not name explicit alternatives (e.g., versus another review/check tool) or state when not to use it, so it falls short of a 5.

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