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

With no annotations, the description carries the full burden and falls short. It does not disclose that the payload must contain either a 'dms' object or a 'decimal' value (and that the null side is required to be null), nor what range validation or error behavior applies. It also says nothing about the return format, though that is arguably minor for a pure conversion.

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?

One sentence, front-loaded with the verb and both conversion directions, with no wasted words.

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?

The input is a required nested payload object with an anyOf union and no schema descriptions, and there is no output schema or annotation to fill the gap. A single sentence is insufficient to make this tool callable with confidence.

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 single parameter is a nested object, so the description must compensate. It usefully implies the two input modes ('decimal degrees' ↔ 'DMS') which map onto the 'decimal' and 'dms' properties, but it omits the direction enum, the range constraints, the required wrapper key, and the mutual exclusivity semantics.

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 names a specific operation and both directions of conversion (decimal→DMS and DMS→decimal), which is clearer than the cryptic name 'geo_dms'. It does not distinguish itself from the other geo_* siblings, but those cover entirely different computations, so the risk of confusion is low.

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?

There is no guidance on when to choose this tool or what preconditions apply. The description only restates the conversion, leaving the agent to infer that it is used whenever DMS formatting is needed.

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