Create a new reusable label on a Trello board with a name and color so you can apply it to cards. Define the label once, then reuse it across cards.
Use when creating a new reusable label on a Trello board before applying it to cards.
| Name | Required | Description | Default |
|---|---|---|---|
| name | Yes | Human-readable label name. | |
| color | Yes | Trello label color. | |
| boardId | Yes | Trello board id containing the labels. |
Changes observed during successful MCP inspections.
v1.0.4Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure, yet it only says this creates something. It does not state whether duplicate names are rejected, what permissions or board scope are required, whether the change is reversible, or what the tool returns.
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?
A single front-loaded sentence beginning with 'Use when', with no redundant restatement of the tool name or schema fields. Every clause carries 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?
For a mutation tool with zero annotation coverage and no output schema, the description is thin: it explains the intent but omits failure modes, permission/board prerequisites, and confirmation of what is created or returned, leaving the agent to infer mutation semantics from the name alone.
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 100% and all three parameters (boardId, name, color, with a 30-value color enum) are documented in the schema itself. The description adds no parameter-level meaning, so the baseline 3 applies.
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 names a specific verb and resource ('creating a new reusable label on a Trello board') and its qualifier 'reusable ... before applying it to cards' implicitly separates it from label-only siblings like label_get/label_update and the combined card_label_create_and_add. It is clear what the tool does, though it never names a sibling explicitly.
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?
'Use when creating a new reusable label ... before applying it to cards' supplies situational context, and the phrase 'before applying it to cards' hints at the two-step workflow versus card_label_create_and_add. However, no alternative is actually named and no when-not-to-use condition is stated, so guidance is implied rather than explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.