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

With no annotations provided, the description carries the burden. It discloses data delay ('one market day delayed'), the inclusion of a regime mode indicating actionability, and the pay-per-call nature of the live sibling. These are meaningful behavioral traits that help an agent set expectations, though it does not mention rate limits or auth requirements.

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 description is a single, dense sentence that packs in all essential details: two lanes, specific scores, flags, regime mode, free tier delay, and the live alternative. It front-loads the core purpose and each clause earns its place, with no fluff.

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?

Given no output schema and no parameters, the description covers the key output elements (scores, flag, note, regime) and the critical distinction between free and live versions. It provides enough context for an agent to decide to call this tool and understand what it will receive.

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 input schema has zero parameters, so the description need not explain parameter behavior. Baseline for 0 params is 4, and the description adds no competing information. It could explicitly state 'takes no parameters' but that is unnecessary given the empty schema.

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 states the tool's function: 'Today's ranked buy-list candidates per book across two lanes' and mentions specific outputs like scores, leadership flag, and entry-window note. It distinguishes from the sibling get_buy_list_live by naming it explicitly, and from other board tools by focusing on buy-list candidates.

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?

It provides clear context for when to use this tool vs. the live sibling: 'Free tier: one market day delayed. Live sibling (x402, pay-per-call): get_buy_list_live.' This implies the free version is for delayed data and the live one for real-time needs, but it does not explicitly state exclusions or alternative non-live tools.

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