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

Annotations cover the safety profile (readOnly, idempotent, openWorld, non-destructive), but the description adds operational traits the annotations cannot express: a 30-second per-wallet chain-read cache, a cost of 3 units, and two failure modes (malformed address is refused; a wallet with no ladders returns an empty list). This is exactly the additional context that justifies a top score.

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-loads purpose and routing, then returns, then behavior, then errors — a clean information hierarchy. The return-field enumeration is long but earns its place because there is no output schema to carry that information.

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 must describe the return payload, and it does so exhaustively (ladders[] field list, history[] semantics with ordering and 50-item cap). Combined with cost, caching, and error behavior, an agent has everything needed to call this correctly without further inspection.

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?

The single address parameter is fully documented in the schema (pattern + description), so the baseline is 3. The description adds value by tying the parameter to observable outcomes — a malformed address is refused and an empty-ladder wallet yields an empty list — which clarifies what the address actually selects.

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?

Opens with a precise verb+resource+scope: 'Reads every live ladder of one wallet across every LoomLadder contract, with its history.' An agent can immediately distinguish this from plan_ladder_action, market_tokens, and my_positions because all three are named in the same paragraph.

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?

Gives an explicit trigger ('when a wallet asks what it holds'), an explicit upstream dependency ('before plan_ladder_action, which needs the ladderId and contract this returns'), and explicit exclusions ('Not for the market (market_tokens) or for Earn positions (my_positions)'). When-to-use, when-not, and alternatives are all covered.

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