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

Annotations already declare readOnlyHint=false, idempotentHint=false, destructiveHint=false, so the agent knows a non-idempotent, non-destructive call. The word "signed" usefully explains why a preview still counts as a mutation (a token is issued), but nothing is said about token lifetime, required permissions for draft previews, or rate limits.

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 — the artifact and scope land first. It is efficient but so terse that it leaves obvious questions unaddressed rather than being maximally helpful.

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?

An output schema exists, so return values need no explanation, and the tool is simple (one required id). The remaining gap is whether viewing a draft preview requires ownership or specific permissions, which for a non-readOnly call an agent would benefit from knowing.

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?

Only one parameter, and the schema documents it at 100% coverage ("Post id to preview."). The description adds no format, lookup, or validation detail beyond the schema, so baseline 3 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?

States a specific verb and output artifact ("Mint a signed preview URL") plus the resource scope (a post, draft or published). This separates it from template-oriented siblings like render_template_preview, though it never names get_post or send_post_test as adjacent alternatives.

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?

The phrase "(draft or published)" implies the tool covers both post states, which is useful scoping. However, there is no explicit when-to-use, when-not, or named alternative among the many post-related siblings (get_post, publish_post, send_post_test).

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