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

Discloses important behavior beyond annotations: the URL is short-lived, one-time-use, expires after 10 minutes, is consumed on download, requires no Authorization header, and only works while the draft is still in draft status and not expired. It also explains that fields without valid coordinates are omitted from the rendered PDF but remain in draft data. This adds substantial operational context beyond the readOnlyHint annotation.

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 detailed but every sentence contributes distinct useful information: purpose, return payload, auth requirement, usage guidance, workflow integration, rendering caveat, and constraints. It is front-loaded with the core purpose and then provides necessary operational context without redundancy.

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 single-parameter tool with no output schema, the description fully covers return values, expiry behavior, authentication, prerequisites, and sibling differentiation. The mention of the typical preview flow also makes the tool's role in a larger process clear and sufficiently 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?

Schema coverage is 100%, so the draftId parameter is already fully described in the schema. The description adds contextual constraints such as draft status and expiry but does not add new parameter-level semantics. Baseline 3 is appropriate given complete schema coverage.

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 and resource: 'get a short-lived, one-time-use download URL for a PDF preview of the draft.' It clearly distinguishes itself from get_draft_file by describing the URL-based output and the condition under which each tool is appropriate.

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?

Explicitly says when to use this tool ('when the MCP client should hand the user a clickable link') and when to prefer an alternative ('If the client can render PDFs inline, prefer get_draft_file'). It also provides a typical preview flow with related tools, leaving no ambiguity about placement in a workflow.

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