cycles_decide

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

With no annotations, the description carries full burden. It discloses key behavior: it does not create a reservation and is a preflight check. However, it omits details on auth requirements, rate limits, or whether it modifies state, which would enhance transparency.

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?

The description is two sentences with no wasted words. It immediately states the purpose and usage guidance, front-loading critical information.

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?

Given the complexity (5 parameters with nested objects), no output schema, and no annotations, the description is relatively brief. It tells the agent what the tool does but not enough about how to correctly invoke it, especially regarding parameter structure and return values.

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 0%, and the tool description adds no information about parameters like idempotencyKey, subject, action, or estimate. The description does not compensate for the lack of schema descriptions, leaving the agent without guidance on how to populate these fields.

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 it is a 'lightweight preflight check' that checks if an action would be allowed without reserving budget, and explicitly says 'Does not create a reservation.' This distinguishes it from siblings like cycles_reserve.

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?

It advises to 'Use at workflow start to decide strategy' and directly names the alternative: 'For concurrency-safe budget locking, use cycles_reserve instead.' This provides explicit when-to-use and when-not-to-use guidance.

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