Zapmail MCP Server

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

No annotations are provided, so the description carries full burden. It states it 'returns' balance, implying a read-only operation, but doesn't disclose behavioral traits like whether it requires specific permissions, if it's cached, rate limits, error conditions, or what 'active workspace' means contextually. This leaves significant gaps for a tool that likely accesses financial data.

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, clear sentence with zero wasted words. It's front-loaded with the core action and resource, making it immediately understandable. Every word earns its place by specifying what is returned and for what scope.

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 lack of annotations and output schema, the description is incomplete. It doesn't explain what the balance value represents (e.g., currency, format), whether it's real-time or cached, or how errors are handled. For a financial tool with no structured safety or output information, more context is needed to ensure reliable use.

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?

The input schema has 0 parameters with 100% coverage, so no parameter documentation is needed. The description appropriately doesn't mention parameters, focusing instead on the tool's purpose. It implies the context ('active workspace') is handled automatically, which is sufficient given the empty 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 specific action ('Return') and resource ('current wallet balance for the active workspace'). It distinguishes from siblings by focusing on balance retrieval rather than billing, subscription, or domain management operations listed among sibling tools.

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 prerequisites (e.g., authentication), frequency considerations, or what to do if balance information is needed for other contexts. The sibling list includes tools like 'get_wallet_balance_13490707e0' which appears similar, but no differentiation is provided.

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