twilio_get_message

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

No annotations are supplied, so the description carries the burden; 'Read' plus the single-message scope makes the read-only, non-destructive nature reasonably clear. The '(Beta)' marker is honest signaling, but the description is cut off mid-list of returned fields and says nothing about errors or permissions for a single-record fetch.

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?

It is a single front-loaded sentence that gets to the verb, resource, and identifier format immediately with no filler. The only defect is the trailing ellipsis, which makes the sentence read as unfinished rather than deliberately compact.

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?

For a simple single-record read with no output schema, the description covers the essentials: what is fetched, by what identifier, and where identifiers come from. Given the total absence of annotations and a schema missing the parameter, the truncated return description leaves an agent without a full picture of the response.

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?

The description explains the one meaningful input (a message SID), including its valid prefixes and where to obtain it, which the empty schema does not. However, the schema declares zero properties, so the described SID parameter is not actually modeled, and the truncated field list leaves the semantic picture incomplete.

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?

The description names a specific verb and resource ('Read one Twilio message by its SID') and identifies the accepted SID prefixes (SM…/MM…), which lets an agent distinguish it from twilio_list_messages or twilio_send_message. The trailing ellipsis truncates the statement of what is returned, so the purpose is clear but not fully stated.

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?

It gives useful routing context by saying SIDs come 'from twilio_list_messages', implying the list-then-get pattern. It never says when not to use it or what to do for a missing/invalid SID, so guidance is implied rather than explicit.

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