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

With no annotations, the description carries the full behavioral burden. It usefully discloses the transport, cost, and payment mechanism (GET /v1/board/crypto, $0.04 via x402) plus a docs link, which is genuine value beyond structured fields. It stops short of disclosing pagination, freshness/latency, or whether limit truncation silently drops markets.

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?

Front-loaded with the core purpose and return contents, and the cost/endpoint metadata is sensibly relegated to a trailing bracket. Slight redundancy across the first two sentences ('all active crypto markets' vs 'one-call board of the most active crypto markets') costs it a perfect score.

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 single-param list tool with no output schema, the description covers purpose, returned fields, drill-down affordance (per-market slugs), and access/cost details. Remaining gaps (pagination behavior, data freshness, explicit sibling routing) are minor for a tool of this complexity.

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?

One parameter (limit) exists with 0% schema description coverage, and the description never mentions it or its range/default. 'Top markets by volume' hints that results are capped, but no meaning is added beyond the schema's min/max/default. Self-evident param keeps this at the baseline.

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 gives a specific verb+resource ('board of the most active crypto prediction markets') and enumerates the returned fields (blended live probabilities, resolution dates, per-market slugs). The 'crypto' domain clearly scopes it within the large probability_board_* family, but it never explicitly distinguishes itself from near-name siblings like probability_board_changes or probability_board_delta.

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 bulk read for agents tracking the state of crypto at a glance' implies the use case (broad situational snapshot rather than a targeted query). However, no when-not-to-use condition is given and no alternative sibling is named (e.g., changes/delta for diffs, probability_calendar_crypto for scheduled events), leaving routing to inference.

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