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

Annotations already declare readOnlyHint=true, and the description adds valuable context beyond that: the baseline is 'last recorded' and can span several rebuilds, and usage is rate-limited with paid overage via x402. This gives the agent a clear picture of operational constraints and semantics.

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?

The main purpose is front-loaded, followed by useful examples and then quota/pricing details. It is slightly dense, especially the pricing clause, but every sentence contributes either to intent, context, or cost behavior.

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 single-parameter, read-only tool, the description gives enough context to invoke it: what it returns, what baseline means, and cost limits. It does not describe the exact output shape, but the 'which symbols entered or left' phrasing adequately conveys the return content.

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?

There is only one parameter, list_id, and its schema description is 100% complete ('Screen id from list_smart_lists whose additions and removals you want'). The tool description adds no extra parameter-level meaning, so the schema carries the full burden and the baseline score 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 clearly identifies what the tool returns: symbols that entered or left a stock screen since its last baseline, with concrete examples like golden crosses and momentum-leader removals. It does not use an explicit imperative verb like 'get' or 'list', and it does not name a sibling tool, but the 'entered or left' framing makes it distinct from get_smart_list and similar list-retrieval tools.

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?

The description implies when to use it: when you need membership changes since a baseline, such as new signals or dropped names. It offers examples but no explicit when-not-to-use guidance or direct comparison with alternatives like get_smart_list or get_smart_list_metrics.

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