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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds meaningful behavioral context: it warns that unseen keys correspond to code paths that acted without asking and that retrying can cause duplicate side effects. It also gives an explicit operational instruction to send references only and never credentials.

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 sentences with no wasted words: the operation, the practical risk, and the security constraint are each addressed. The most important semantic is front-loaded, and the guidance is directly actionable.

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 two-parameter, no-output-schema tool with strong annotations, the description covers the operation, the business rationale, and the risk model. The main gap is the undocumented 'effect_type' parameter, which prevents the description from being fully self-sufficient.

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 50%: only 'keys' has a description, while 'effect_type' is undocumented. The description clarifies that keys are the vendor-reported idempotency keys, but never explains what effect_type means or what values it accepts. The description partially compensates for the missing schema coverage but leaves a required parameter meaningfully unexplained.

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 uses a specific verb ('returns') and resource ('idempotency keys for actions a vendor says actually happened') and clearly separates the two outcomes: went through Ratchet vs. never seen. This distinguishes it from sibling tools like ratchet_list_effects or ratchet_get_effect, which inspect stored effects rather than reconcile external facts against them.

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 intended scenario is explicit: you have idempotency keys from a vendor and want to find actions that bypassed Ratchet. The description does not name alternative tools or state when not to use it, but the context is clear enough that an agent can infer this is for reconciliation rather than for inspecting a single effect or listing effects.

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