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

Annotations only declare readOnlyHint=true, so the description usefully adds the data provenance (monthly IRS EO BMF extract), the exact sample size (10 organizations), the lookback window (3 months before the newest batch), and the returned field set. It does not mention authoritative freshness or rate limits, but for a read-only sampling tool this is solid supplementary disclosure.

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?

A single front-loaded sentence that leads with the resource and scope before drilling into the payload contents and the 'Free' qualifier. Dense but every clause adds information; it is long, yet nothing is clearly disposable.

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 full return-value burden and does so by listing the aggregate stats, the 10-org sample, the up-to-100 organization records and their fields. Combined with the readOnly annotation, an agent has enough to call it correctly, though the fresh/paid alternative remains unexplained.

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 100% and there is only one parameter ('state', documented as a two-letter code with example TX). The description adds 'for one state', matching the schema, but provides no extra format or constraint detail. Baseline 3 is appropriate when the schema carries the parameter 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 states a specific resource (new US tax-exempt organizations from the monthly IRS EO BMF extract), a scope (one state), and enumerates exactly what is returned (count, categories, 10-org sample, up to 100 orgs recognized in the prior 3 months with field list). It clearly separates itself from leads/trucking/liquor siblings by resource, but never names its closest relative new_nonprofits_fresh, so the fast/full vs sample distinction is left to inference.

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 trailing 'Free' and the 'sample' naming imply this is a preview variant, and the phrase 'for one state' implies the required scoping, but there is no explicit when-to-use or when-not-to-use guidance. The obvious alternative, new_nonprofits_fresh, is not named or routed to, leaving selection to inference.

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