Get an NYC zoning district

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

Annotations already cover read-only/idempotent/non-destructive/openWorld, but the description adds real behavioral context: the exact data scope covered and the caveat that height/setback detail is limited to what NYRezone publishes. The unknown-code fallback behavior is also disclosed, which is useful for an open-world tool.

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?

Three tight sentences, front-loaded with what is returned, then the data caveat, then the error path. No filler, though the payload enumeration is slightly list-heavy for a one-parameter call.

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 an output schema present, return values need not be spelled out, yet the description still orients the agent on fields and adds the null/unknown-code path. Complete enough for a simple lookup; only the sibling-routing is left unstated.

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% with one parameter, so the baseline is 3. The description repeats the same example codes (R6A, C4-2, M1-2/R6A) already given in the schema and adds no new syntax, format, or case-handling detail beyond it.

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?

Specific verb ('Get') plus resource ('the rules NYRezone publishes for one NYC zoning district code'), and it enumerates the payload (max FAR, base/maximum height, bonuses, lot counts, average built FAR). The scope word 'one ... code' implicitly separates it from list_zoning_districts, but no sibling is named explicitly.

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 (supply a district code to get its rules) and the description adds an error-path hint that an unknown code returns valid codes. It never states when to prefer this over list_zoning_districts or lookup_lot, so guidance stays at implied-usage level.

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