Zaim API MCP Server

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

With no annotations provided, the description carries full burden but only states it creates records without disclosing behavioral traits. It doesn't mention whether this is a write operation requiring specific permissions, if it's idempotent, what happens on failure, or any rate limits. For a mutation tool with zero annotation coverage, this is a significant gap.

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 a single, efficient sentence in Japanese that clearly communicates the tool's purpose. It's appropriately sized with zero wasted words and front-loads the essential information about creating transfer records.

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 mutation tool with no annotations and no output schema, the description is insufficient. It doesn't explain what happens after creation (success response format, error conditions), doesn't mention authentication requirements despite zaim_check_auth_status being a sibling, and provides minimal behavioral context for a write operation.

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 all parameters are documented in the schema. The description adds no additional parameter semantics beyond what's in the schema. The baseline score of 3 is appropriate when the schema does the heavy lifting for parameter documentation.

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 action ('作成します' - creates) and resource ('振替記録' - transfer record) with the context of being between accounts. It distinguishes from siblings like zaim_create_income and zaim_create_payment by specifying it's for transfers between accounts rather than income or payments.

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 implies usage context by specifying '口座間の資金移動' (fund transfers between accounts), which helps differentiate from income/payment creation tools. However, it doesn't explicitly state when to use this versus alternatives or mention any prerequisites like authentication status.

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