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

Annotations are absent, so the description carries the full burden. It only states 'Fetch a single SMS template by id' and does not disclose behavioral traits such as read-only nature, error handling (e.g., 404 if not found), response format, or any permissions needed. 'Fetch' implies a read, but this is not explicit.

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?

The description is a single, front-loaded sentence with no wasted words. It states the action and the key parameter immediately, making it easy to parse quickly.

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 one-parameter get tool with no output schema and no annotations, the description covers the basic action but omits return behavior, error cases, and any usage context. It is minimally viable but leaves gaps that an agent might need, such as what a successful response contains.

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 0% and the description only says 'by id', which adds minimal meaning beyond the parameter name 'id'. It does not explain the format, constraints, or what the id refers to beyond the obvious. The description fails to compensate for the lack of schema documentation.

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 'Fetch a single SMS template by id' clearly specifies the verb (fetch), the resource (SMS template), and the scope (single, by id). This distinguishes it from sms_templates_list (which would fetch multiple) and other sms_templates_* siblings without needing to open the schema.

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?

No guidance is given on when to use this tool versus alternatives. There is no mention of 'use sms_templates_list to get all templates' or any exclusions or prerequisites. The intended usage is only implied by the tool name and the phrase 'by id'.

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