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

With no annotations, the description carries the full burden and does well: it discloses the sending address, thread continuity, and flags the irreversible real-world effect ('This emails a real customer'). It omits prerequisite state (must the draft be pending?), permission requirements, and what happens to the draft record afterwards.

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?

Three short sentences, front-loaded with the action and scope, then the optional parameter behavior, then a one-line warning. Every sentence adds information and nothing is padded.

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 mutation tool with no annotations and no output schema, the description covers what happens to the customer and how to edit content. It could do slightly more on preconditions and on what a caller gets back (confirmation or sent-message id).

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 coverage is 50%: body is described but draft_id is not. The description partially compensates by explaining that body replaces the drafted text with an edited version, while draft_id's meaning ('a pending draft') is only implied. Baseline 3 for mid coverage is appropriate.

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+resource ('Approve a pending draft and send it') plus the delivery channel ('same email thread from the product's support address'), which cleanly separates it from the sibling Support_Decline_Draft.

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 makes clear the tool acts on a pending draft and that passing body sends an edited version, which is actionable context. It never explicitly names Support_Decline_Draft as the alternative path for rejecting a draft, so the when-not guidance is implied rather than stated.

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