karte-datahub-mcp

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions that the tool 'gets the count' which implies a read-only operation, but doesn't specify whether it requires authentication, has rate limits, returns paginated results, or what happens with null parameters. The default date values are mentioned, but other behavioral aspects are undocumented.

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 well-structured with a clear purpose statement followed by parameter documentation. Each parameter explanation is concise and informative. While efficient, the Japanese-only text might limit accessibility for non-Japanese speaking agents, and the structure could be slightly improved with clearer section headers.

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 that an output schema exists, the description doesn't need to explain return values. However, for a 4-parameter counting tool with no annotations, the description should ideally provide more behavioral context about what 'count' means (e.g., is it aggregated counts when using group_by?). The parameter documentation is excellent, but overall context about the tool's behavior remains incomplete.

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?

With 0% schema description coverage, the description fully compensates by providing clear semantic information for all 4 parameters. It explains what each parameter does, provides example syntax ('event_name = "purchase"'), specifies date format requirements (YYYYMMDD), and documents default values (2 days ago for date_from, yesterday for date_to). This adds significant value beyond the bare schema.

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 states the tool's purpose: 'KARTEイベントの件数を取得する' (Get the count of KARTE events). It specifies the verb ('取得する' - get/count) and resource ('KARTEイベント' - KARTE events), making the purpose unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'query_karte_events' which might also retrieve event 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 provides no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'query_karte_events' or 'execute_karte_sql', nor does it specify use cases, prerequisites, or exclusions. The parameter documentation implies filtering and grouping capabilities, but no contextual usage instructions are provided.

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