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

Goes well beyond the annotations by disclosing the authentication model (personal access token created by the business owner under Settings, AI assistants, sent as a Bearer header) and the read scoping ('reads only that business's own call and text log'), which agents cannot infer from readOnlyHint alone.

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 action and scope, then content detail, then the auth prerequisite. It is a dense run-on sentence, but each clause (delivery status, median call-to-text-back time, 50-text cap, token requirement) carries real information.

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 no output schema, the description compensates by describing what comes back: delivery status as reported by the phone, the median time from call to text-back, and up to 50 most recent texts with wording. Auth and read-scoping are also covered, so nothing needed for correct invocation 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 coverage is 100% and the enum already documents each range value, so the description adds nothing about parameter semantics beyond restating 'in a time range'. Baseline 3 applies when the schema does the heavy lifting.

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 ('List the texts your Ringback line sent') and enumerates the content types (missed-call text-backs, dashboard replies, automatic replies), which clearly distinguishes it from the sibling my_missed_calls.

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?

The scope ('your Ringback line sent in a time range') makes clear when this tool applies and implicitly separates it from the missed-calls sibling, but there is no explicit guidance on when to prefer an alternative or what to do when the range is insufficient.

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