sms_invalid_phones

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

With no annotations, the description carries the full behavioral burden, yet it discloses nothing about read-only nature, authentication requirements (apiKey/restEndpoint), rate limits, pagination behavior, or return shape. For a 7-parameter tool with no output schema, this is a substantial gap.

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?

A single, well-formed sentence with zero filler and the key scope constraint front-loaded. It is efficient, though its brevity contributes to the under-specification elsewhere rather than being a model of tightness.

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 7 parameters, zero annotations, and no output schema, the definition should say more: pagination/limit behavior, auth expectations, result format, and the relationship to the remove sibling. Almost all of that is missing.

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%, so every parameter is already documented in the schema. The description only echoes the date-range concept behind start_date/end_date and adds no syntax, defaults, or format details beyond that, so the baseline of 3 applies.

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 ('Query'), a precise resource ('phone numbers marked as invalid'), and a scope ('within a date range'). The purpose is clear on its own, but it never distinguishes itself from the closely related sibling sms_invalid_phones_remove, which a reader must disambiguate unaided.

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?

There is no when-to-use guidance, no exclusions, and no mention of the natural alternative sms_invalid_phones_remove for clearing invalid numbers. Usage is only implied by the verb 'Query'.

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