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

Annotations already flag destructiveHint=true and idempotentHint=false, but the description adds high-value context beyond them: the sitelink is an account-level asset so edits propagate to EVERY linked campaign and ad group, unpassed fields retain their values, and descriptions must be set as a pair or neither. These are exactly the consequences an agent needs before mutating.

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?

Dense but every sentence earns its place: the in-place edit statement is front-loaded, followed by use cases, discovery method, mutation semantics, the account-level warning, and the dry-run flag. No filler or repetition despite the length.

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 7-param destructive mutation with 0% schema coverage, the description covers discovery, partial-update semantics, field constraints, blast radius, and dry-run. An output schema exists, so return values need no explanation. Nothing needed to invoke it correctly is missing.

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 0%, so the description carries the burden and does: it explains link_text, description1/description2 (with the pair constraint), final_url repointing, asset_id sourcing, and confirm as dry-run. Character limits (25/35) add constraints absent from the schema. Only customer_id is left implicit, which is trivial.

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 ('edits') and resource ('an EXISTING sitelink') plus the exact editable fields (link text, two description lines, URL). Explicitly distinguishes itself from delete-and-recreate workflows and from create tools, so an agent can pick it over siblings like manage_extension_assets or remove_extension_assets.

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?

Gives concrete when-to-use scenarios (adding missing descriptions, fixing a typo, repointing a moved landing page) and names the discovery tools (list_extension_assets, list_assets(asset_type='SITELINK')) to obtain the required asset_id. It also documents the dry-run switch (confirm=false), leaving nothing to inference.

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