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

With no annotations, the description carries the full burden and does a good job: it discloses no sending, no credit cost, and 'sample' implying no real side effects. It could add what 'id' refers to or note whether the agent must exist, but the core behavioral transparency is solid.

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 sentences with no waste: the action and key safety qualifiers are front-loaded, and the use case is stated compactly.

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 one-parameter, no-output-schema preview tool, the description covers purpose, safety, and timing well. The output form is implied by 'render a sample email,' which is sufficient for a low-complexity tool.

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 schema has a single undocumented 'id' parameter at 0% coverage. The description's 'from this agent' implies id is the agent identifier, adding some meaning beyond the bare schema, but it never explicitly states the parameter's role or any format/existence requirements.

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 ('Render'), object ('sample outreach email'), and source ('this agent'), and clearly distinguishes itself from sending tools by stating no sending. It also stands apart from preview_linkedin_followup and preview_linkedin_invite by focusing on the agent's own email.

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 explicit context: use this to check tone/script before launching, and it emphasizes no sending and no credit cost so an agent can safely choose it for pre-launch review. It doesn't enumerate alternatives or exclusions, but the intended timing is clear.

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