Tick or untick a checklist item

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

Annotations already disclose readOnlyHint=false and destructiveHint=false, so the agent knows this is a non-destructive write. The description adds the id-provenance routing detail, but says nothing about auth requirements, whether the change is reversible, or what a successful mutation returns — reasonable extra context but not rich disclosure.

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, the action stated first and the id-provenance prerequisite second. No filler, no restatement of the tool name, nothing wasted.

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 3-parameter mutation with annotations and no output schema, the description covers the action and the key parameter provenance. It omits what a caller should expect back after ticking an item (e.g. updated checklist state) and any permission/error context, leaving noticeable holes for a write tool.

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 67% (in the middle band), and the schema already explains cardId formats and constrains state via enum. The description adds real value by clarifying where checkItemId comes from (trello_get_card) and paraphrasing state. That is meaningful but not compensating for the remaining undocumented surface.

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+resource ('Mark a checklist item complete or incomplete'), so the action is unambiguous. It also names the sibling that supplies the required identifier ('Item ids come from trello_get_card'), giving partial sibling orientation, but it does not contrast itself with any alternative tool the way a 5 would.

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?

The prerequisite for checkItemId (obtain it via trello_get_card) is implied, and 'complete or incomplete' frames the two cases. However, there is no explicit when-to-use/when-not guidance, no note about required permissions, and no alternative tool named for other checklist operations.

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