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

Annotations already declare readOnly, idempotent and non-destructive behavior, so the description only needs to add context. It does contribute the required permission scope ("Needs tasks.read"), which is genuine added value, but says nothing about result shape or pagination behavior beyond what the schema documents.

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 clauses, front-loaded with the action and resource, then the usage rationale. No filler and no repetition of schema or annotation content.

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 simple two-parameter read tool with no output schema, the description covers purpose, the triggering context, and the auth requirement. A brief note on what a label contains would close the remaining gap, but an agent has enough to call 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 description coverage is 100% and both limit and offset are thoroughly documented there, including the string-vs-numeric cursor rule. The description adds nothing about parameters, which meets the baseline but no more.

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 ("List the task labels") and adds a parenthetical explaining what labels are for, which separates it from sellsy_list_tasks. It does not explicitly name the sibling it differs from, but the resource is distinct enough that confusion is unlikely.

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 parenthetical "a label id is required to create a task" tells the agent exactly when to reach for this tool — before sellsy_create_task. It stops short of naming alternatives or exclusions, but the usage trigger is concrete.

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