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

Annotations already grant read-only/idempotent/no-destructive, and the description adds real value beyond them: Friday update cadence with holiday caveat, which quarters are returned, inclusion of 50%/80% intervals, publisher narrative, and concluded-quarter nowcast vs. BEA actuals. That is exactly the behavioral context an agent needs to trust and schedule the call.

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?

Front-loads the identity and scope before the return-value detail, and every sentence conveys usable information. It is a dense single paragraph with mild redundancy in the FRED disclaimer, but nothing is wasted.

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?

With no output schema, the description carries the burden and delivers: it enumerates the returned fields (headline percentage, intervals, narrative, concluded-quarter comparison) and the refresh schedule. An agent can call it and interpret results without further documentation.

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 coverage is 100% and both optional parameters (include_history, history_quarters) are fully documented in-schema, so the description adds nothing about parameters. Baseline 3 applies when the schema does the work.

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 resource (NY Fed Staff Nowcast), a specific measure (weekly real GDP growth nowcast, annualized QoQ), and scope (currently-tracked US quarters). It also explicitly separates itself from the fred_* siblings by noting FRED's catalog does not carry this series.

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?

Gives concrete trigger phrasings ("what is the NY Fed GDP nowcast", "current GDP growth estimate") and an exclusion (not a FRED series), which clearly routes the agent away from the fred_* family. It does not name a specific sibling alternative by tool name, so it stops short of full when/when-not routing.

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