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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so safety needs no restating. The description adds real behavioral detail beyond them: exact league codes are required, unknown start times are excluded by the time filters, and output rows switch shape based on view. Pagination behavior and rate limits are left implicit, which keeps it at a 4.

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 tool's purpose and primary value, then moves through filters, time-boundary rules, and output shape in a logical order. It is dense but each clause carries information; only the repeated view/compact explanation overlaps with the schema.

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?

With 11 parameters, no output schema, and heavy filtering, the description covers the return row shape (flat fields vs nested objects), the tier labeling, and the inclusive/exclusive time boundary rules. An agent has enough to call it correctly without opening the schema, and the annotations cover safety.

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 description coverage is 100%, so the schema already carries the parameter burden and baseline is 3. The description does reinforce a few semantics the schema also states — exact league codes only, start_after inclusive vs start_before exclusive, unknown starts excluded, view=full for nested objects — but adds little that is not already in the schema text.

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 ('get current PrizePicks lines') and adds a positioning claim ('the first place to get current PrizePicks lines') that distinguishes it from the many sibling read tools like get_board_at, get_changes, and get_line_history. It also names the filtering axes and the tier labeling, so an agent knows exactly what this tool returns.

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 phrase 'The first place to get...' gives a clear default entry point when the agent wants current lines, and the description enumerates the filter combinations that select this tool (league, stat, player/team search, tier). It stops short of naming explicit alternatives or when-not-to-use conditions, so it falls just below the top score.

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