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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, indicating safe read-only behavior. The description adds value by detailing the response structure (tracked[], expired[], snapshot_dates[]), explaining the meaning of fields like trend and decay_pp_per_day, and noting limitations (TTL, snapshot gaps). No contradictions with annotations.

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 dense but well-organized: it starts with a high-level purpose, then details the response format, and ends with limitations. While it packs a lot of information into a few sentences, it remains clear and avoids redundancy. Some extra punctuation and capitalization could be improved, but overall efficient.

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?

Despite lacking an output schema, the description fully explains the response fields (tracked, expired, snapshot_dates) with detailed semantics, including sub-fields like edge_pp_net time-series, trend, decay_pp_per_day, first_seen, and lifespan_days. It also covers behavior (snapshot gaps, TTL) and parameter effects. This is complete for a read-only tool with two parameters.

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%. The description adds context beyond the schema by explaining default values (days default 14, max 30; window default '1wk'), providing a purpose for each parameter (days as lookback, window as snapshot family), and clarifying constraints (days clamped 2-30). This fully compensates for any missing schema 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?

The description clearly states the tool provides 'edge persistence and decay telemetry' from daily snapshots, answering specific questions about how long an edge has existed and whether it's shrinking. It distinguishes itself from sibling tools like 'polymarket_edges' by focusing on historical tracking rather than just current edges.

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 understand edge persistence and decay) and provides a concrete example contrasting a fresh wide edge vs. a 3-week-old one. It also includes a LIMITS section indicating constraints like history depth and snapshot gaps. While it doesn't explicitly state when not to use it, the context and sibling references imply alternatives like 'polymarket_edges' for current data.

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