Update draw.io diagram

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

Annotations only indicate that the operation is not read-only and not idempotent; the description adds meaningful behavioral context by stating it writes a separate output unless overwrite is explicitly enabled. This alerts the agent to the default non-destructive side-effect behavior, which is valuable beyond annotations.

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?

Two dense sentences convey the operation scope and the overwrite behavior with no filler. The most decision-relevant fact—that output is separate unless overwritten—is stated and placed at the end without bloating the definition.

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 mutation tool with no output schema and sparse parameter documentation, the description is adequate but not comprehensive. It provides the key operation summary and overwrite caveat, but does not help an agent construct valid operations or understand how output_path/overwrite interact in edge cases, leaving gaps compensated only by the raw schema.

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 should carry parameter semantics, but it only mentions add nodes/edges/update-node operations at a high level. It does not explain input_path, output_path, overwrite semantics, or operation object requirements, leaving significant inference to the agent despite a fairly nested schema.

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?

Description clearly states the action: add nodes/edges or update a node in an existing draw.io file. It names the resource ('existing draw.io file') and distinguishes it from creating a new diagram, though it does not explicitly differentiate from inspect_diagram or validate_diagram.

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 'existing draw.io file' conveys that this tool is for modifications rather than creation, and the separate-output note helps agents avoid unintended file overwrites. No explicit when-not-to-use or alternative routing is provided, but the context is clear enough for most selection decisions.

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