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

With no annotations to fall back on, the description carries the behavioral burden well: it discloses ordering, cursor-based pagination, archive depth, per-call cost, and x402 settlement. It could also explain the response shape and exactly what 'both bases' means, but the provided behavioral detail is strong for an unannotated tool.

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 dense but every sentence earns its place: result orientation, parameter example, pagination rule, archive depth, and pricing. It is front-loaded with the core purpose and wastes no words.

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?

Given the moderate complexity and absence of an output schema, the description provides enough operational detail for an agent to invoke the tool correctly, paginate through results, and understand archive limits. The main gap is the exact response field layout, which would be more important if this were a more complex or less self-describing API.

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 100%, so the schema already documents all four parameters. The description adds a compact URL-style example and restates defaults, but it does not materially add meaning beyond the schema. Baseline 3 is appropriate.

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 clearly identifies the resource (kimchi premium time series), the source (continuous archive), the ordering (newest-last), and coverage (both bases). It stops short of a 5 because it lacks an explicit verb like 'returns' or 'fetches' and does not directly name a sibling tool for comparison, though 'continuous archive' implies historical vs. current data.

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 gives clear operational context: how to paginate with next_before, how to read a full window, and how archive depth is reported. It does not explicitly state when to use this tool instead of kimchi_premium or kimchi_premium_stats, but the historical-archive framing makes the intended use reasonably clear.

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