listCategoriesRetrieve all calendar category names defined in Thunderbird preferences to get exact, case-sensitive names before creating tasks or events.
Return all calendar category names defined in Thunderbird preferences. Use this before creating tasks or events to get exact category names (case-sensitive).
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds useful behavior beyond that: the source of truth is Thunderbird preferences and the returned names are case-sensitive. It does not say whether the result is an array of strings or how empty/preferences-less cases behave, and there is no output schema to cover that gap.
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 tight sentences: the action and data source first, then the workflow guidance. Every clause earns its place and the important constraint (case-sensitivity) is included without padding.
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 zero-parameter read-only tool with full annotation coverage, the description supplies everything needed to call it correctly, including the case-sensitivity caveat. The only missing piece is the return shape (a list of names), which is a small gap given there is no output schema.
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?
The tool takes zero parameters, so the baseline is 4. The description correctly implies no inputs are needed, and there is nothing further to document.
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 and resource: 'Return all calendar category names defined in Thunderbird preferences.' The mention of 'category names' distinguishes it from the sibling listCalendars, which returns calendars rather than categories, so an agent can route without opening either schema.
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 clear when-to-use guidance: call it before creating tasks or events to obtain exact category names. It does not name an alternative tool or state when not to call it, which keeps it short of a 5, but the intended workflow context is explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.