bubblyphone-agents

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

Annotations cover safety profile (readOnly, non-destructive, idempotent), but the description adds valuable return value context: 'Returns numbers with pricing information.' This discloses what data to expect since no output schema is provided. It also clarifies these are inventory/available numbers, not owned ones.

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 sentences efficiently structured: purpose (sentence 1), filtering capabilities (sentence 2), and return values (sentence 3). Zero redundancy—every sentence adds distinct information not found in the structured fields. Appropriately front-loaded with the core action.

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?

Given 100% schema coverage and present annotations, the description is appropriately scoped. It compensates for the missing output schema by mentioning 'pricing information' in the description. Could be improved by noting that all parameters are optional (0 required) or mentioning the limit default/max behavior.

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?

With 100% schema description coverage, the baseline is 3. The description mentions filtering by country, area code, and locality, conceptually grouping three parameters, but adds no semantic details for number_type, contains, or limit that aren't already in the schema. It meets but does not exceed the baseline.

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?

Description clearly states the tool searches for 'available phone numbers to purchase,' using a specific verb and resource. It effectively distinguishes from siblings like buy_phone_number (purchase action), get_phone_number (retrieve specific owned number), and list_phone_numbers (list existing inventory) by emphasizing 'available' and 'to purchase.'

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?

While the phrase 'to purchase' implies this tool precedes buy_phone_number, there is no explicit guidance on when to use this versus list_phone_numbers (for owned numbers) or get_phone_number (for specific number details). The workflow relationship with the purchase tool is left implicit.

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