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

Annotations already cover read-only, idempotent, non-destructive and closed-world, so the bar is lower. The description adds genuine behavioral context beyond that: the result is limited to the top 3 per book, headline fields only, and delayed by one market day. These freshness/scope constraints are the key non-obvious traits and are disclosed.

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?

Leads with the resource and ranking, then fields, then the awareness block, then the sample/delay caveat. Dense but front-loaded and mostly waste-free, though the parenthetical explanations add minor verbosity.

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?

There is no output schema, so the description must carry the return-value burden, and it does – enumerating price, day change, opportunity percentile band, entry state, and the awareness block (sector money flows, coverage, coiled-setup count). Coverage is strong, with only the exact response shape and pagination left unspecified.

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 are no parameter semantics to explain and the baseline is 4. The description adds no misleading parameter detail.

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?

Specific verb (get) and resource (market leaders) with a rich description of scope: top 3 per book across US stocks, ETFs and crypto, ranked by opportunity score, with named fields. It distinguishes itself from most siblings by content, but the obvious live counterpart get_market_leaders_live is only implicitly distinguished via 'one market day delayed' rather than named directly.

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 'Free sample... one market day delayed' clause implies this is the delayed/sample variant and hints at when to use it, but there is no explicit when-to-use guidance or named alternative (get_market_leaders_live). Usage is left for the agent to infer from the delay note.

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