List plan definitions

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

Annotations already declare readOnlyHint=true, so the read-only nature is covered. The description adds useful context about the tool returning raw stored fields rather than date-resolved entries, but it doesn't mention any other behavioral aspects like ordering, pagination, or whether all definitions are returned. This is minimal but reasonable given the simple read-only nature.

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, well-structured sentence that front-loads the core action and resource, then adds a parenthetical detail and a contrast with the sibling tool. No wasted words.

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 listing tool with no output schema, the description is complete. It specifies the action, the resource, the key output fields, and the distinction from the sibling tool, which is all the agent needs to decide and invoke 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?

The tool has zero parameters, so schema coverage is effectively 100% with no properties to describe. The baseline for no params is 4, and the description adds value by enumerating the fields present in the output, which gives the agent an idea of what to expect without needing parameter details.

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 clearly states the tool lists the user's day-planner block definitions and names the specific fields (recurrence rule, scheduled time, active_from). It also explicitly distinguishes this from list_daily_plan_blocks by noting the result is not resolved against a specific date, making the purpose and scope unambiguous.

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 description provides a clear contrast with list_daily_plan_blocks, signaling when to use this tool (when you need stored definitions rather than date-resolved blocks). This gives the agent a direct decision rule for choosing between sibling tools.

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