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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered, but the description adds no behavioral context of its own: no return shape, ordering, pagination, or whether results are site-scoped. It only restates the purpose in list form.

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 front-loaded sentence with no filler or redundancy. It is appropriately sized for a lookup, though its brevity is partly the source of the documentation gaps rather than deliberate economy.

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 two-parameter read-only lookup with no output schema, the description does identify the returned content (sender identities and templates), but it leaves both required scoping parameters and any usage context undocumented, making it only minimally complete.

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?

Both parameters (projectId, siteId) are required with 0% schema description coverage, so the description carries the full burden of explaining them — yet it never mentions either parameter or what scope they impose on the returned identities and templates.

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 ("List") and a specific resource set ("sender identities and templates"), with the scope qualifier "a new draft can use" that narrows it below the sibling list_outreach_templates. Clear purpose, though it never names a sibling to contrast with.

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?

Usage is only implied: the phrase "a new draft can use" suggests calling this before create_outreach_draft or prepare_outreach_draft, but no explicit when-to-use, prerequisites, or alternative (e.g. list_outreach_templates) is given.

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