gmail_list_templates

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, and the description's 'Read-only, no I/O' merely restates them. The only added semantic content is 'built-in', which clarifies these are fixed server-side templates rather than user-created ones, but no return shape or template metadata is described despite there being no output schema.

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?

Two short sentences with the core purpose front-loaded; nothing needs to be read twice. The second sentence is largely redundant with the annotations, which is minor waste but not harmful.

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 zero-parameter, read-only list tool this is close to sufficient, but with no output schema the description should say what a returned template looks like (name, id, locale, body?) and whether the list is fixed. As written, an agent knows the intent but not the payload.

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 tool takes zero parameters and the schema is an empty object, so there is nothing for the description to disambiguate. Baseline for a parameterless tool 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?

The description uses a specific verb and resource ('Lists built-in composition templates') and even gives three example template names, so the agent knows exactly what comes back. It does not, however, differentiate from the closely related sibling gmail_render_template, leaving the list-vs-render distinction implicit.

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 statement of when to call this versus the obvious alternative gmail_render_template, nor any prerequisite or sequencing hint (e.g. 'call this first to discover valid template names'). Usage is only inferable from the tool name.

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