diagram_patch

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

With no annotations available, the description carries the behavioral burden. It does well by revealing a non-obvious behavior: 'Do not supply x/y; draw.io layout places new cells' and 'Coordinates belong to the editor, not the model.' It does not disclose broader mutation consequences like idempotence or validation behavior, which keeps it from being a 5.

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 short, front-loaded, and wastes little space: it opens with purpose and immediately gives the actionable coordinate warning. The final sentence, 'Coordinates belong to the editor, not the model,' is conceptually useful but somewhat redundant with the preceding sentence, preventing a full 5.

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?

The description is reasonably complete for a small patch tool: it names the supported edit types and warns against a common invalid input class. Missing context includes how the 'layout' parameter behaves, how references between operations are resolved, and what kind of response or effect to expect for a nuanced nested operations array.

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 schema description coverage is 0%, so the description must compensate. It partially compensates by enumerating the operation types and explaining that coordinates should not be user-supplied. However, it never mentions the 'layout' parameter, which is one of only two parameters, omitting meaningful guidance about what layouts do or when to choose them.

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 uses a specific verb and resource: 'Apply a few structured edits (add_node, add_edge, set_label)'. It clearly identifies what the tool does at a glance. It does not explicitly contrast itself with sibling tools like diagram_replace, so it falls short of a perfect 5.

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 phrase 'Apply a few structured edits' implies this tool is for incremental changes rather than wholesale replacement, giving some contextual usage signal. However, it does not explicitly state when to prefer diagram_patch over diagram_replace or any other sibling tool, and it provides no exclusions or alternative routing.

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