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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely useful behavioral context beyond that: the tool takes no arguments and is the entry point, and the section choices trade breadth ('states' in brief, 'full' as everything) against depth ('state:<CODE>' in full), which hints at payload size. It does not describe response format or potential truncation of 'full'.

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 contents enumeration is front-loaded, then the 'call this first' directive, then the section breakdown — a sensible order for an agent. It is somewhat dense and the section list duplicates the schema's parameter description almost verbatim, which is wasted space, but nothing is irrelevant.

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 of telling the agent what comes back, and it does: a catalog of coverage, metrics, dimensions, analyses, planning schema, rules and examples, with granularity controls. Missing are the response format and the practical size of 'full', but for a one-optional-parameter discovery tool this is nearly complete.

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 the single parameter's schema already documents 'Omit for the federal catalog' plus every section value. The description restates this with the same examples ('state:MA'), adding a small amount of reinforcement but no meaning beyond the schema. Baseline 3 applies when the schema does the heavy lifting.

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 both the verb (get) and the resource, then enumerates the concrete contents: data coverage, metrics, dimensions, analyses, the QueryPlan JSON schema, planning rules and worked examples. It also distinguishes itself from siblings by positioning itself as the entry point ('Call this first'), which is enough for an agent to tell it apart from run_plan, search_far, etc.

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?

'Call this first (no arguments)' is an explicit sequencing directive that tells the agent exactly when to reach for this tool. It also explains how to choose the section value ('states' in brief vs 'state:<CODE>' in full vs 'full'). It stops short of stating when not to call it (e.g. repeated calls, or that discovery should precede run_plan), so it is not a full 5.

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