fetch_observation

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It adds value by detailing the return fields ('input/output, token usage, model, latency, and cost'), but it does not disclose error handling, authentication needs, or any side effects. The verb 'Get' implies a read-only operation, but edge cases are not addressed.

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 long, front-loaded with the core function, and every sentence adds value. It efficiently communicates the action and the key return fields without unnecessary verbosity.

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 simple retrieval tool, the description is mostly adequate, especially given that an output schema exists. However, the 'project' parameter is unexplained, and there is no disambiguation from the similarly named 'fetch_observations' (plural). These gaps make the description less complete than it could be.

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%, so the description must compensate for parameter meaning. The description explains 'observation_id' implicitly ('by ID') but completely omits the 'project' parameter, leaving its purpose unknown. This is a significant gap for a tool with only two parameters.

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 the tool's function: 'Get a single observation by ID.' This specifies a verb ('Get'), a resource ('observation'), and a scope ('by ID'). It also distinguishes from the sibling tool 'fetch_observations' (plural) by emphasizing 'single observation.'

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 description implies when to use the tool (when you have an observation ID and need full details) but does not explicitly mention alternatives or when not to use it. It lacks references to sibling tools like 'fetch_observations' for listing multiple observations, so the usage guidance is only implied.

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