DM20 Protocol

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

With no annotations provided, the description carries full burden. It discloses key behavioral traits: it's a read-only visualization tool (implied by 'Render', 'Shows'), returns ASCII art format, and has specific error/edge case behavior ('No tactical map active'). However, it doesn't mention rate limits, authentication needs, or what happens when highlight_aoe is provided.

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?

Perfectly concise with two focused sentences. First sentence states core functionality, second covers edge cases. Zero wasted words, front-loaded with primary purpose, and every sentence earns its place by adding distinct value.

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?

For a visualization tool with one optional parameter, no annotations, and no output schema, the description provides adequate context. It explains what the tool does, the output format (ASCII art), and error conditions. However, it doesn't describe the grid coordinate system or how participants are represented, which could be helpful given the combat context.

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%, so the schema already documents the single optional parameter. The description doesn't add parameter information beyond what's in the schema, but with only one optional parameter and high schema coverage, this is acceptable. The baseline would be 3, but the tool has 0 required parameters which elevates the score.

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 with specific verbs ('Render', 'Shows') and resources ('current tactical map', 'positions of all combat participants on a grid'). It distinguishes itself from siblings by focusing on visual representation of combat state, unlike data retrieval or management tools in the sibling list.

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 clear context for when to use the tool ('if no positions are set or no combat is active' returns specific message), but doesn't explicitly state when NOT to use it or name alternatives. It implies usage during active combat scenarios but lacks explicit exclusions or comparisons to other combat-related tools.

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