Himalaya MCP Server

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

No annotations are provided, so the description carries the full burden. It mentions the default return (plain text body) and parameter effects (headers, raw), but lacks critical behavioral details: it doesn't specify error handling (e.g., if envelope_id is invalid), permissions required, rate limits, or whether the operation is idempotent. For a read 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 appropriately sized and front-loaded: the first sentence states the purpose, followed by return behavior and parameter details. Each sentence adds value, with no redundancy. However, the parameter list could be more integrated into prose for better flow, though it remains efficient.

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 complexity (5 parameters, 0% schema coverage, no annotations, but with an output schema), the description is moderately complete. It covers parameters well and mentions the default return, but lacks behavioral context like error handling or permissions. The output schema likely details return values, so the description doesn't need to explain returns, but overall gaps remain for a tool with multiple parameters and no annotations.

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 0%, so the description must compensate. It adds meaningful semantics for all 5 parameters: envelope_id is the ID to read, folder defaults to INBOX, account uses default if omitted, headers includes message headers, and raw returns MIME content. This goes beyond the schema's titles (e.g., 'Folder' vs 'Folder name. Defaults to INBOX'), providing clear usage context.

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: 'Read a message by its envelope ID' specifies the verb (read) and resource (message). It distinguishes from siblings like message_thread (which handles threads) and envelope_list (which lists envelopes). However, it doesn't explicitly differentiate from all siblings, such as template_forward or template_reply, which are write operations.

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 when to prefer message_read over message_thread for single messages, or when to use envelope_list for listing instead. There's no context about prerequisites or exclusions, leaving the agent to infer usage from the purpose alone.

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