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

Annotations already flag destructiveHint=true and idempotentHint=true, but the description goes further and explains concretely what destruction means: the draft leaves drafts_awaiting_photos, its finish_url stops opening it, and listing_add_photos can no longer complete it. It also documents the dry-run gate ('without confirmed: true nothing changes and the draft is described back'), which is real behavioral context beyond the annotations.

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?

Three sentences, zero filler, front-loaded with the destructive effects before the constraints and the edit-workaround. Every clause carries distinct information an agent needs.

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?

Even without an output schema, the description explains what the call does, what it irreversibly affects, the account scoping, the confirmation requirement, and the dry-run response. 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 100%, so the parameter baseline is 3, but the description adds meaning by explaining the confirmed dry-run contract (nothing changes and the draft is echoed back) rather than merely restating the boolean. The draft_id is left to the schema, which already names its sources.

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 (discard) and resource (draft), plus the exact scope: drafts that listing_create saved without photos. It distinguishes itself from siblings by naming listing_add_photos and listing_create directly, so an agent can select it without opening any schema.

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 covers when to use it and the alternative path: since a draft can't be edited, the description instructs the agent to discard and recreate when a change (e.g. a new price) is needed. It also states the eligibility constraint (only this account's own connector drafts) and the confirmation prerequisite.

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