Get Fiber Readiness

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

Annotations already declare read-only/idempotent, and the description adds substantial behavioral context beyond them: PeeringDB is global but thin outside dense US/EU metros, 'unknown' is not 'bad', and carrier_data_coverage determines whether score and single_carrier_risk are null. It explicitly warns not to report a 'none_in_region' site as greenfield, unserved, or build-required—information annotations cannot convey.

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 core purpose and a concrete example; every sentence earns its place, including the counter-intuitive 'unknown' caveat and sibling exclusions. It is long, but the density of consequential detail—null semantics, coverage distinction, and bucket meanings—justifies the length.

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?

Covers the full call context: what the tool returns, what each bucket means, when values are null, and when to use alternatives. Even with a rich output schema, the description adds interpretive semantics (e.g., 'unknown' vs 'confirmed', single-carrier risk) that the structured schema cannot express, so an agent has everything needed to call and interpret the result correctly.

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 coverage is 100%, so the baseline is 3, but the description adds value by explicitly marking lat and lon as required even though the schema's required array is empty, and by tying radius_km to 'reachable fiber carriers' with default and range. It also gives a concrete example invocation with parameter values, reinforcing meaning beyond the schema.

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 and resource: 'get the FIBER-READINESS / connectivity verdict for ONE parcel or site (lat/lon)' with concrete outputs (near-net distance, carrier count, single-carrier risk). It also distinguishes itself from siblings by naming what it is not: route mapping and full multi-factor suitability.

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?

Explicitly scopes usage: 'Use when you need the FIBER-READINESS / connectivity verdict for ONE parcel or site' and gives exclusions with named alternatives: 'Do NOT use to map carrier ROUTES between metros (use get_fiber_intel) or for a full multi-factor site suitability score (use analyze_site).' Also clarifies the critical 'unknown' vs 'no carrier' interpretation, which is essential for correct use.

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