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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds 'Score-blind' and a note that the reserve lives in wire('tape'), but both are cryptic fragments whose operational meaning is unclear rather than genuinely informative.

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 short and front-loads the 'Game-coin ledger' framing. But telegraphic fragments ('Score-blind.', 'The reserve is wire('tape').') trade clarity for brevity, so the terseness costs comprehension rather than earning its place.

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 one-parameter read tool whose annotations already cover safety and idempotency, the description supplies the return content for both modes and identifies the data source. The main remaining gap is its relationship to the sibling read_ledger, but the core calling information is present.

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 0% for the single 'what' parameter, so the description must carry the load — and it does define the two documented values ('supply' and 'flux') with their semantics. However, it does not state whether those are the only legal values or enumerate alternatives, leaving gaps against the 0% coverage.

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 opening 'Game-coin ledger' plus the mode breakdown ('supply': minted, burned, circulating per coin; 'flux': sinks vs sources per day) tells an agent this reads coin-economy statistics. But the tool name 'spoils' is opaque, there is no title, and no verb is stated outright. It also fails to differentiate itself from the sibling read_ledger, which sounds closely related.

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 the two mode values but never says when to pick this tool over read_ledger or wire, nor what prerequisites apply. The reference to wire('tape') is a pointer, not routing guidance for this tool.

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