generate_diagram

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

With no annotations, the description carries the full burden and does well: it discloses that layout is automatic (do NOT compute x/y), that 'replace' clears existing content while 'append' preserves it (a destructive-behavior disclosure), and that the target must already exist. It stops short of describing failure modes or what the call returns.

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?

Front-loaded with the core purpose, then cleanly sectioned into NODES / EDGES / MODE blocks that map to the parameters. It is somewhat long, and lines like 'Every important relationship should be an edge' echo the preceding sentence, but no section is wasted.

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 annotations and no output schema, the description supplies the crucial missing behavioral context (auto-layout, destructive replace semantics, prerequisite that the diagram exists). It does not say what happens on invalid node/edge references or what the agent gets back on success.

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 coverage is already 100%, so baseline would be 3, but the description adds genuine semantic guidance beyond the schema: how many nodes/edges to create and on what basis (one per distinct component, one per data flow/API call/dependency), plus edge-labeling intent. It largely restates the mode and diagram_id meaning already given in the 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?

The opening sentence names a specific verb (generate) and resource (visual diagram) and states the source (structured graph of nodes/edges) and destination (existing CanvasKeep diagram). It clearly distinguishes itself from create_diagram by requiring an existing diagram_id and pointing to create_diagram for setup.

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?

It gives concrete usage instructions: supply logical structure only, let CanvasKeep handle layout, one node per component, one edge per meaningful interaction, and explains replace vs append. It references create_diagram as a prerequisite for obtaining the diagram_id, but never states when NOT to use this tool versus siblings like save_diagram_scene or update_diagram.

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