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

Beyond the readOnly/idempotent/destructive annotations, the description discloses that scores derive from counters only the settlement path can write, that the evidence trail is a public hash-chained log verifiable without credentials, and that amounts are never emitted. These are concrete behavioral facts not present in the annotations. Nothing in the text contradicts the annotations.

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 front-loaded with purpose and usage, but it carries esoteric internal cross-references (CO 200, CO 571, CO 472) and rhetorical framing ('a fact surfaced, not a verdict rendered') that an agent cannot act on without external context. It is informative but could be tightened without losing meaning.

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 supplies complete return shapes for both the leaderboard and single-tenant modes, defines what `evidence` is, and covers the read-only safety profile. Paired with parameter routing and sibling guidance, everything an agent needs to invoke and interpret the tool 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 coverage is 100%, so the baseline is 3, but the description adds meaning by mapping each parameter to an outcome (omit for the whole board, platform= for vendor filtering, tenant_id= for a single rank) and by showing how the result shape changes between modes. This goes beyond the schema's type-level descriptions.

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 sentence defines a specific resource and operation: a live ranking of agent-run businesses by a settlement-derived track record. It explicitly differentiates from sibling catalog tools with 'the catalog is how you enter; the arena is how you're ranked,' which lets an agent distinguish it without opening other schemas.

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 maps each invocation mode to a goal: 'Omit args for the top of the board; platform= to filter by vendor type; tenant_id= for one business's rank.' It also names the sibling alternatives (federation_catalog_agents / federation_catalog_platforms) and states the condition that selects them versus this tool, so routing is explicit.

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