Price a new destination

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

Annotations already declare readOnlyHint=true and openWorldHint=true; the description reinforces the read-only contract with 'Changes nothing' and adds a confirmation workflow that annotations cannot express. It stops short of covering failure modes such as an unresolvable address or what the preview contains beyond price.

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 tight sentences with no wasted words, and the non-mutating guarantee is front-loaded right after the purpose. The trailing workflow instruction is slightly imperative in tone but still 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 two-parameter, non-destructive preview with no output schema, the description conveys what the agent gets back (a new price) and how to act on it. A brief note on what happens when the destination cannot be geocoded would make it fully complete.

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 the schema itself documents the ride_id omission default and the four accepted destination forms including coordinate and landmark lookup. The description adds no parameter meaning beyond that, 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 and resource — pricing the active ride against a different destination — and implicitly contrasts with change_destination by framing this as a preview that 'changes nothing'. An agent can distinguish it from the sibling mutation tool without opening any schema.

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 names the alternative ('call change_destination only if they agree') and the condition that selects it, plus an ordering rule (show the user the new price first). This is the when/when-not pattern at its clearest.

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