convert_eml_to_bundle

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 states that the tool creates a directory, copies the .eml, leaves the source untouched, and returns a JSON structure with specific fields. It also discloses that move/delete modes are rejected. However, it does not mention potential side effects like overwriting existing directories, error handling, or permissions. Still, the core mutation and side-effect profile is clear, warranting a 4.

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 about 120 words, organized into a brief purpose statement, a note on source_handling, and a return-value summary. It is not excessively verbose and front-loads the core action. Some redundancy exists (e.g., stating the return format), but it remains appropriately sized for the complexity.

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?

Despite an output schema (which the description partially covers by naming returned fields), the tool has 15 parameters and 0% schema description coverage. The description only addresses source_handling, leaving the meaning of presets, thread modes, and all boolean flags unexplained. This is a significant gap for an agent to invoke the tool correctly with the full range of options.

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 only explains source_handling, noting the 'copy' limitation. The other 14 parameters (preset, thread_mode, thread_order, boolean flags) are left undefined. The description adds value for one parameter but fails to clarify the vast majority, leaving agents without essential meaning for the options they may set.

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: converting an .eml file into a self-contained bundle with markdown and attachments. It uses a specific verb and resource, but does not differentiate from sibling tools like convert_eml or convert_directory. The purpose is unambiguous, earning a 4 rather than a 5 because it lacks explicit sibling differentiation.

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 a constraint on source_handling (only 'copy' is accepted over MCP, with guidance to use CLI/API for other modes) but does not explain when to choose this tool over its siblings. There is no mention of convert_eml, convert_directory, or get_diagnostics as alternatives for different scenarios. The guidance is parameter-specific rather than tool-selection-focused.

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