freeagent_create_mileage_expense

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

Annotations already indicate mutability (readOnlyHint=false, destructiveHint=false). Description adds behavioral details: rate selection logic involving env vars, HMRC threshold, and distance API dependency. Could be improved by noting error handling or return value.

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-paragraph structure with front-loaded main purpose. Every sentence contributes necessary detail. Could be slightly more compact, but overall efficient and well-organized.

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?

Covers core functionality and key parameter interactions. Lacks information about return values (e.g., created expense ID) and error handling (e.g., invalid address, failed API call), which would be helpful given no output schema.

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 has 100% parameter description coverage. Description adds value beyond schema by explaining parameter interdependencies (origin/destination vs manualMiles, roundTrip, cumulativeMilesYTD with threshold logic). Enhances understanding of conditional behavior.

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?

Clearly states 'Create a mileage expense in FreeAgent' with specific verb and resource. Distinguishes from sibling tools like freeagent_create_expense by focusing on mileage-specific logic (origin/destination vs manualMiles, rate defaults, roundTrip).

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?

Provides explicit instructions for when to use origin+destination vs manualMiles, and explains ratePence vs environment variable defaults. However, does not directly compare to freeagent_create_expense or advise when not to use this tool.

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