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

Annotations already declare it is a non-readonly, non-idempotent, open-world write that is not destructive. The description adds real context beyond that: the page is public via slug, there is only one page per authenticated creator, and blocks are 'safe' link/title/text types. It does not say what happens on a second create call, which matters given idempotentHint=false.

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 tightly packed sentences that lead with the action and resource, then the constraints. No filler or restatement of the title.

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?

With an output schema present, return values need not be described, and the schema fully documents parameters. The remaining gap is the create-once failure mode and the absence of any pointer to link_in_bio_update for subsequent modifications.

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 description coverage is 100% and all ten parameters have field-level docs, so the baseline is 3. The description echoes the client_id requirement for new blocks, which the schema already states, so it adds emphasis rather than new meaning.

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 clear verb (Create) and resource (the authenticated creator's link-in-bio page) with the key scoping word 'single'. It implicitly tells the agent this is a one-per-creator resource, though it never names link_in_bio_update or link_in_bio_upsert_block as the tools for later edits.

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?

No explicit statement of when to use this versus link_in_bio_update or link_in_bio_import_linktree. The 'new blocks require client_id' clause hints at the create-vs-upsert distinction but leaves the agent to infer it from sibling names.

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