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

With annotations already declaring readOnlyHint, openWorldHint, and idempotentHint, the description adds valuable behavioral context: the 60-day snapshot TTL, cache-miss snapshot writing causing gaps, and decay computed from daily closes net of default slippage. It also explains the response structure, which exceeds what annotations alone convey.

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 several sentences but well-structured with labeled sections (Args, RESPONSE, LIMITS). Every sentence carries information, but the length is slightly more than necessary; it could be condensed. It is organized and front-loaded with the purpose.

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?

There is no output schema, so the description thoroughly documents the response fields (tracked, expired, snapshot_dates), their meanings, and limitations (TTL, daily closes). It even provides interpretation guidance (e.g., 'median lifespan is your competition clock'), making it fully self-contained.

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% for both parameters. The description repeats defaults and enum values already in the schema, only adding the 'snapshot family' concept and the 'cache-miss' reason for snapshot gaps. This adds minimal meaning beyond the schema, so the baseline of 3 applies.

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 defines the tool as 'Edge persistence and decay telemetry built from daily polymarket_edges snapshots' and poses a direct question it answers ('how long has this edge existed and is it shrinking?'). This distinguishes it from siblings like polymarket_edges (current edges) and polymarket_arbitrage.

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 provides clear context: it explains that a fresh wide edge and a 3-week-old wide edge are different trades, implying when persistence/decay analysis is needed. However, it does not explicitly name alternative tools or state when NOT to use this tool.

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