find_business_by_phone

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

Annotations already indicate read-only and idempotent. Description adds behavioral details: results limited to 'a handful of candidates', empty list means not found. This clarifies nondeterminism and false negatives beyond annotations.

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?

Two sentences, zero filler. First sentence defines purpose and usage context. Second sentence covers format and output expectations. Every phrase earns its place.

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 1 parameter and no output schema, description covers all essential aspects: action, usage scenario, input format, and result interpretation. No gaps for agent decision-making.

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 100% and schema already describes phone format thoroughly. Description merely reaffirms format without adding new meaning. Baseline 3 is appropriate.

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?

Clear verb 'look up' and resource 'Yelp businesses' with specific filter 'phone number'. Differentiates from siblings like 'search_businesses' (generic) or 'get_business' (by ID) by focusing on phone lookup.

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?

States when to use: 'when you have a phone number and need to identify the business'. Provides format requirement (E.164) and explains return behavior (few candidates, empty if not found). No explicit when-not, but context implies it's the dedicated phone lookup.

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