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

Annotations already declare readOnly/idempotent/openWorld, so the safety profile is covered; the description goes further by disclosing return characteristics (bounded, paginated rows with 2010 GEOIDs, source hash, IRS authority) and a 2010-versus-2020 boundary warning. This is genuinely useful behavioral context beyond the annotations, though pagination limits are not quantified.

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 core question, then scope, return shape, and caveats; each sentence carries distinct information. It is dense with detail but no sentence is pure filler, though the vintage warning is repeated in two forms.

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 appropriately covers the return shape and pagination, and it addresses the tool's main risk (vintage/GEOID confusion). It is essentially complete for an agent to call it correctly, missing only concrete pagination bounds.

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%, so the schema already explains all seven parameters including enums and defaults. The description only gestures at the jurisdiction/county/tract-type filters without adding syntax or semantics beyond the schema, which is the expected baseline when structured fields do 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 verb (searches designations) and resource (final 2018-cycle Qualified Opportunity Zone designations), and frames the tool's role as discovery, which cleanly separates it from the lookup/compare/summarize siblings. An agent can identify the resource and its cycle vintage without opening the schema.

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 explicit usage direction ('Use for discovery') plus two meaningful exclusions: don't use a 2020-vintage GEOID and don't confuse this with the still-unfinalized 2027 cycle. It does not explicitly name the alternative sibling tools (lookup/compare/summarize) the way a perfect routing statement would, so it falls just short of 5.

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