Create a Niche Dive from a Competitor List

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

Annotations only flag destructiveHint=true; the description adds substantial context the annotations cannot: tokens are spent per ASIN, the action is irreversible, it is NOT safe to retry (each call starts a separate dive and spends again), and the correct recovery is polling `get_dive_status`/`list_niches`. It further enumerates the no-cost failure modes (over plan limit, account niche limit, insufficient Amazon data) and the async return contract.

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?

Front-loaded with the usage condition and the sibling contrast, then warnings. Every sentence carries unique operational information (cost, irreversibility, retry hazard, failure modes, async polling), though the description is dense enough that it approaches the upper end of what 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?

For a destructive, token-spending, asynchronous tool with no output schema, the description covers the full lifecycle: cost warning, retry prohibition, recovery path, failure cases, and the returned `diveId`/`estimatedCompletionDate` plus polling loop to `success`/`nicheId`. Nothing an agent needs to invoke it safely 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 description coverage is 100% and all three parameters already carry inline descriptions covering the 2-200 ASIN bound, the `confirm` cost-approval semantics, and the marketplace enum domain. The description largely restates these bounds rather than adding new parameter meaning, so the baseline of 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?

The description gives a precise verb+resource ('builds the niche from the given ASINs only') and explicitly distinguishes itself from the sibling `create_niche_dive`, which 'discovers competitors around one seed ASIN'. An agent can route between the two without opening either 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?

States the exact triggering condition ('when the user already knows which products belong in the niche — e.g. they list competitor ASINs, or picked them from search results') and names the alternative for the other case. It also states the confirmation prerequisite, so the when-to-use decision is fully specified.

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