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

The description discloses validation before storage, refusal with reasons and nothing written on malformed nets, and the exact return payload (new id, applied ops, diff). This goes well beyond the annotations (which only hint at destructive potential) and adds no contradiction.

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 front-loaded with the core purpose and then systematically lists operations, validation behavior, and return values. It is somewhat long due to the operation catalog, but every section earns its place and is logically ordered.

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 complex tool with a variable operations array and no output schema, the description covers invocation, exact operation shapes, validation, failure atomicity, and return values. An agent has everything needed to call it correctly without further reference.

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 description enumerates each operation type and its required fields (add_place, add_transition, etc.), giving the operations parameter rich semantics far beyond the schema's generic 'JSON array of operations'. This significantly helps an agent construct valid input.

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 it applies structural edits to a stored model and stores the result as a new owned model with lineage, which is a specific verb+resource+outcome. It enumerates the full operation vocabulary, distinguishing it from creation, comparison, and deletion 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?

It provides strong context: edit a stored model, receive a new model, use the same operations as the guided builder. However, it does not explicitly name when not to use it or how it differs from siblings like sim_create_model or sim_supersede_model, so it falls short of full 5.

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