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

With no annotations, the description carries the full behavioral burden. It partially meets it by disclosing what the digest is composed of and that alerts are threshold-driven, which tells the agent this is a composite read. It says nothing about rate limits, freshness/caching, cost of the call, or whether any filters reorder or suppress digest sections.

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?

A single sentence that front-loads the core purpose and then lists the four digest sections in order. No redundancy; 'built for agents' is the only phrase of marginal value, but it is not enough to undermine an otherwise tight structure.

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?

For a zero-annotation, no-output-schema tool, the description usefully conveys the return shape by enumerating the four sections, which is the right move. It still leaves gaps: the role of each numeric parameter, the ordering/truncation behavior of the list, and the fact that the 48h window is fixed rather than configurable.

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 only 33%: alert_pp is documented in the schema, while limit and min_volume_24h have no description at all. The description partially compensates by tying '1-hour move alerts above a threshold' to alert_pp and 'top markets by 24h volume' to the volume filter, but it never explains what limit bounds or how min_volume_24h interacts with the mover/alert sections.

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?

Names a specific resource (Polymarket market digest) and enumerates the exact contents: 24h-volume leaders, 1-day movers, 1h move alerts, and liquid markets ending within 48h. This is clearly distinguishable from a single-market tool, but it never explicitly positions itself against the overlapping siblings top_markets and biggest_movers, whose data it apparently bundles.

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 framing 'compact digest... built for agents' implies a use case (a one-call overview rather than a targeted lookup), and the 48h/alert contents hint at a monitoring scenario. However, there is no explicit when-to-use statement and no exclusion or routing guidance relative to top_markets, biggest_movers, or search_markets.

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