DM20 Protocol

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 'active rulebooks' and 'current campaign', which adds some context, but fails to disclose critical behavioral traits such as whether this is a read-only operation, what format the output takes (e.g., list, pagination), or any permissions required. The description is minimal and lacks operational details.

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 no wasted words. It is front-loaded with the core action ('List all active rulebooks') and efficiently specifies the context ('in the current campaign'), making it easy to parse and understand quickly.

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 simplicity (0 parameters, no output schema, no annotations), the description is adequate but has gaps. It covers the basic purpose and scope but lacks details on output format, behavioral traits, or usage guidelines. For a read operation in a campaign context, more context on what 'active' means or how results are structured would enhance completeness.

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 tool has 0 parameters, and schema description coverage is 100%, so there are no parameters to document. The description appropriately doesn't discuss parameters, and the baseline for 0 parameters is 4, as it avoids unnecessary detail while matching the schema's completeness.

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 ('List all active rulebooks') and the resource ('in the current campaign'), providing a specific verb+resource combination. It distinguishes from siblings like 'load_rulebook' or 'unload_rulebook' by focusing on listing rather than loading/unloading, though it doesn't explicitly contrast with them.

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 like 'search_rules' or 'get_library_toc', nor does it mention prerequisites (e.g., needing an active campaign). It only states the scope ('in the current campaign') without explicit usage context or exclusions.

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