DM20 Protocol

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

No annotations are provided, so the description carries full burden. It mentions the tool 'Returns the full hierarchical table of contents extracted from the PDF or Markdown source, with page numbers and content types,' which adds useful behavioral context about output format. However, it lacks details on permissions, rate limits, error conditions, or whether this is a read-only operation, which is important for a tool interacting with library sources.

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, with the core purpose stated first. The additional details about return format and parameter guidance are useful but could be slightly more streamlined. There's no wasted text, but it's not perfectly concise.

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 tool's moderate complexity (single parameter, no output schema, no annotations), the description is adequate but has gaps. It explains what the tool does and the parameter, but without annotations or output schema, it should ideally provide more behavioral context (e.g., read-only nature, error handling). It meets minimum viability but lacks completeness for optimal agent 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?

Schema description coverage is 100%, with the schema fully documenting the single parameter 'source_id'. The description adds minimal value beyond the schema by repeating the parameter explanation and providing an example ('e.g., 'tome-of-heroes'' is in the schema). Since the schema does the heavy lifting, the baseline score of 3 is appropriate.

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: 'Get the table of contents for a specific library source.' It specifies the verb ('Get'), resource ('table of contents'), and scope ('specific library source'). However, it doesn't explicitly differentiate from sibling tools like 'list_library' or 'search_library', which prevents a perfect score.

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 implied usage guidance by mentioning 'use list_library to see available sources' for the source_id parameter. This suggests when to use this tool (after identifying sources via list_library), but it doesn't explicitly state when to choose this tool over alternatives like 'extract_content' or 'search_library', nor does it provide exclusion criteria.

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