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

Annotations already establish readOnly/idempotent/non-destructive, so the description only needs to add behavior, which it does: it defines what qualifies as the cohort ($1k+ realized PnL over 5+ resolved markets) and what each mode measures. It does not describe the shape of a returned signal row or how 'meaningfully below mid' is thresholded, which is the remaining gap for a tool with no output schema.

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?

Three sentences, each carrying distinct payload: capability, mode semantics, cohort definition. The core purpose is front-loaded and there is no repetition of schema defaults or annotation facts.

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 all four parameters optional, 100% schema coverage, and safety already covered by annotations, the description supplies the domain context an agent needs to choose a mode and interpret results. It falls short only on output expectations (what a signal contains, ranking direction) for a tool with no output schema.

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 coverage is 100%, so baseline would be 3; the description earns above baseline by expanding the terse enum label 'Signal type' into a real explanation of what each mode computes, and by framing 'hours' as the lookback window driving the flow ranking. It says nothing about category or the 20-row cap beyond what the schema documents.

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+resource ('Detect smart-money signals on Polymarket') and then decomposes it into two named modes with distinct semantics, so the agent knows exactly which capability it is invoking. It also defines the central term ('cohort') inline, removing ambiguity that sibling tools like polymarket_tape or polymarket_markets would not cover.

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 two modes are each qualified with a condition that selects them: 'flows' for largest net cohort inflow over N hours, 'mispricings' where cohort bought meaningfully below current mid. That is clear internal routing guidance, but there is no explicit statement of when to prefer this tool over siblings such as polymarket_tape, polymarket_market_stats, or wallet_discover.

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