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

Annotations already declare readOnlyHint=false, destructiveHint=false, and idempotentHint=true, so the safety/idempotency profile is covered. The description adds genuine behavioral context beyond that: the state change halts execution and spending, and it is non-destructive ('Nothing is deleted'). It does not explain what happens to already-queued work, which would be the next useful detail.

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 clauses, zero waste, with the core effect front-loaded and the non-destructive reassurance second. Nothing to trim.

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 state-changing mutation tool with no output schema, the description is adequate but thin: it does not say whether the plan can be resumed (activate_autopilot_plan) or what happens to in-flight or scheduled items. Annotations cover safety and idempotency, which limits the gap, but more operational context would help.

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 planId, workspaceId, and idempotencyKey are each documented in the schema (including the idempotency retry semantics). The description adds no parameter-level detail, 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?

States a specific verb (pause) and resource (plan) and describes the effect: 'it stops running and spending.' The closing 'Nothing is deleted' distinguishes it from the destructive sibling delete_autopilot_plan. It does not, however, explicitly name activate/delete/update as the sibling set, so the differentiation is inferential rather than spelled out.

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?

There is no explicit when-to-use guidance or named alternative; the agent must infer that this is the reversible counterpart to delete_autopilot_plan. The 'Nothing is deleted' clause implies when NOT to use delete, which is useful context, but no direct routing statement is present.

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