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

With no annotations, the description carries the full burden and does well: it discloses that data is read from recorded history with 'no fetch, no waiting, no egress spent', that rows carry mine/competitor flags, and that positions must be read alongside depth_scanned. It does not state pagination, result-size limits, or what happens when a term has no recorded history — a meaningful gap for a history-backed read.

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 purpose in the first sentence, then routing, then capability, then the auth note — a sensible order. Slightly literary phrasing ('who was on it, in what order, and which way each of them moved') costs a little density but every section still conveys usable information.

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?

No output schema and no annotations means the description must supply everything, and it covers data source, freshness semantics, auth requirements, fallback tools, and the caveat that positions are only meaningful with depth_scanned. An agent has what it needs to call this correctly and interpret the result.

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 already 80%, so the schema documents term, store, locale, window and extension_id without help. The description adds context about what rows contain (flags, depth_scanned) but does not explain the 'window' boolean or locale behavior beyond what the schema states. Baseline 3 is appropriate.

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 and resource ('the search page for one of an extension's tracked keywords, as this account last recorded it') and enumerates what the result contains (who, order, movement over the past week). It explicitly distinguishes itself from the sibling search_store, so an agent can route without opening a 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?

Directly names the alternative and the selecting condition: 'Use search_store instead when you need what the store is showing right now; use this when you want movement.' It also gives fallbacks for unauthenticated callers (find_listing, get_store_listing) and states the account prerequisite.

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