vm_cancel_ttl

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

Annotations already indicate a write operation and non-destructive behavior; the description adds specific context: 'only removes the schedule and never touches the VM itself.' This clarifies the scope beyond the raw annotation flags without contradicting them.

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?

Three short sentences with no filler. The [WRITE] marker and action are front-loaded, followed by return type, prerequisite, and safety clarification—each sentence earns its place.

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 one-parameter operation with an output schema and annotations, the description covers purpose, return behavior, prerequisite, and non-destructive scope. Nothing necessary for correct invocation is missing.

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 coverage is 100% for the single parameter, so the baseline is 3. The description adds the practical requirement to obtain the 'exact vm_name' via vm_list_ttl, which goes beyond the schema's generic parameter description.

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: 'Cancel an existing TTL for a VM' with the effect 'prevents auto-deletion.' The mention of vm_list_ttl for the exact vm_name disambiguates it from the related TTL tools in the sibling set.

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?

Explicitly instructs the agent to 'Use vm_list_ttl first for the exact vm_name,' establishing the correct precondition. It does not explicitly state when not to use this tool, but the workflow context is clear and actionable.

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