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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds real context beyond that: it is Pro tier only, it returns an empty items[] rather than erroring when nothing is starred, and the result is informational and not financial advice. Missing auth/failure-mode detail keeps it short of a 5.

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 purpose is front-loaded in the first sentence and each subsequent line earns its place (empty-state behavior, tier gating, disclaimer). The multi-line Returns block partly duplicates the existing output schema, which is mild redundancy but also usefully explains field meaning like the ai_score_band ordering.

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 parameterless, read-only tool with a published output schema and full annotation coverage, the description supplies the remaining pieces an agent needs: entitlement (Pro tier), empty-state handling, and result interpretation. The only gap is the lack of explicit differentiation guidance versus similar read siblings.

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?

The tool takes zero parameters, so there is no parameter semantics to explain and the baseline of 4 applies. The description correctly signals the no-argument nature by describing a caller-scoped, implicit-scope retrieval.

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 concrete verb+resource: retrieves the caller's Stocklake watchlist, defined as starred symbols from the web dashboard, plus the enrichments applied. This clearly distinguishes it from list-style siblings such as get_stocks and from per-symbol siblings like get_stock, so an agent can pick 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?

Usage is only implied: it is the watchlist of the calling user, and the description notes that starring happens on the web dashboard, plus what happens when nothing is starred. There is no explicit when-to-use-this-instead-of guidance against siblings like get_stocks or get_signals, and no exclusions.

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