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

With no annotations, the description carries the full burden and does well: it discloses provenance (FRED/ALFRED), states that 'revisions never pose as print-day numbers', and explains the surprise methodology including the market-implied vs trend-model fallback. It also surfaces an operational trait (price $0.02 via x402). It stops short of describing staleness/latency or pagination for the mini-series.

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-loaded with the key noun phrase and structured as capability list plus operational footer. It is somewhat repetitive, restating 'latest print, revisions, surprise' twice ('latest print, revisions, surprise' then 'first-release vs latest value ... surprise vs a labeled expectation'), and the bracketed HTTP/price/docs line is dense but useful.

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?

There is no output schema and no annotations, so the description fully shoulders the burden — and it enumerates the return shape (first-release vs latest value, revised flag, surprise, next monthly release date, 12-observation mini-series). An agent knows exactly what it will receive and can call it correctly with no arguments.

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 tool takes zero parameters, so per the baseline this scores 4. Nothing in the description contradicts or must compensate for a parameter schema that does not exist.

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 verb+resource+scope: 'Core PCE inflation (BEA, monthly): latest print, revisions, surprise.' It also distinguishes itself from the generic sibling by noting it is the 'same shape as /v1/econ/:series bound to core-pce', making it differentiable from econ_series and econ_series_core-cpi despite 200+ siblings.

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?

Usage is implied through the data it returns (latest print, revisions, surprise, next release date) rather than stated. It never says when to prefer this over econ_series_pce-inflation or econ_series_core-cpi, so routing among the near-identical econ_series_* siblings is left to inference from the series name.

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