Update Link In Bio Profile

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

Annotations already flag destructiveHint=true and idempotentHint=true, so the bar is lower; nonetheless the description explains *why* it's destructive ("an empty title or bio removes it", "null removes it") and clarifies partial-update semantics. It does not mention the dry_run preview path, which would have fully closed the loop on the mutation risk.

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 tight sentences, zero filler, with the primary action and mutation semantics front-loaded and the per-field constraints packed into parentheses. Nothing is redundant with 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?

For a 5-parameter mutating tool with no output schema, the description covers what changes, what gets removed, and image format/size limits. The one meaningful gap is the `dry_run` preview option, which for a destructive tool is worth surfacing in prose rather than only in the schema.

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 60%, and the description compensates by adding meaning the schema lacks: the empty-string removal behavior, the data: URL acceptance, and the 5 MB ceiling. It leaves `dry_run` and the required `domain` unaddressed, but those are documented in the schema, so coverage is adequate.

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 ("Set") and enumerates exactly which fields of the Link in Bio profile are affected (title, bio, avatar), which implicitly separates it from siblings like update_link_in_bio_appearance and update_link_in_bio_socials. It never names those siblings or draws the boundary explicitly, so the differentiation is inferential rather than declared.

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?

"Only the fields sent change" gives useful partial-update context an agent can act on, and "up to 5 MB" implies guardrails. But there is no explicit when-to-use / when-not guidance, no mention of the sibling tools that update other aspects of the same page, and no prerequisites stated.

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