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

Annotations already indicate read-only, idempotent, open-world, and non-destructive behavior. The description adds substantial context: it reads from daily snapshots, uses daily closes (not intraday), explains missing data meaning, and clarifies that decay numbers come from daily closes of edge_pp_net. No contradictions.

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 long but well-structured: it starts with the core purpose, then details the response shape, and ends with limitations. Every sentence adds value, though some technical details could be slightly more concise.

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 no output schema, the description fully explains the response structure (tracked with fields, expired with lifespan, snapshot_dates) and data limitations (60-day TTL, snapshot gaps). Given the tool's complexity (2 optional params), this is very complete.

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?

Input schema covers both parameters with descriptions (100% coverage). The description adds meaning by clarifying defaults (days default 14, window default '1wk'), constraints (days clamp 2-30, window options 24hr|1wk|1mo), and how they affect the response. This goes beyond the 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 purpose: to answer 'how long has this edge existed and is it shrinking?' and details the outputs (tracked, expired, snapshot_dates). It differentiates from sibling tools like polymarket_edges and polymarket_arbitrage by focusing on edge persistence and decay.

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 description explains when to use the tool (to distinguish fresh wide edges from old ones) and provides context on data limits (60-day TTL, snapshot start). It does not explicitly state when not to use it or mention alternatives, but the context is sufficient.

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