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

With only readOnlyHint=true in annotations, the description carries substantial extra context: it documents the returned object shape, latest-only behavior, out-of-snapshot error behavior, third-party licensing refusals, and the need for an Oxford Ledge API key. This goes well beyond the annotation and gives the agent the operational and access constraints it needs.

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 long and dense, but the length is justified by the tool's licensing, auth, and output-shape complexity. It is generally front-loaded with the core purpose before exceptions, though the all-caps refusal section is somewhat run-on.

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?

Given the lack of an output schema, the description adequately explains the return object for successful and error/refusal cases. It also covers licensing restrictions and API-key requirements, leaving little ambiguity for an agent trying to call the tool correctly.

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?

The schema already documents the single series parameter at 100% coverage with examples, so baseline credit applies. The description adds meaningful constraints beyond the schema by indicating the parameter must identify a series in the snapshot and that specific FRED ids such as BAMLH0A0HYM2, VIXCLS, and UMCSENT are refused.

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 action and resource: retrieving one FRED macro series from Oxford Ledge's snapshot by FRED id. It clearly distinguishes scope from history-oriented or curve-oriented siblings by stating it returns the newest observation only, never history.

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?

It defines when the tool is appropriate: one series from the approximately 41-series snapshot, identified by FRED id, with latest-only output. It also states key exclusions such as series outside the snapshot and licensed series that are refused, though it does not explicitly route the agent to an alternative sibling tool.

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