execute_command

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

With no annotations provided, the description carries the burden of disclosing behavior. It adds meaningful details beyond 'executes a command': it states that canvas updates immediately and the action is added to undo history. This provides operational awareness, though it could also mention error handling or response behavior, so it falls short of 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 three sentences, each with a clear purpose: definition, mode compatibility, and a usage preference plus behavioral notes. It is front-loaded with the core action and avoids any redundant filler. Perfectly concise for a tool of this complexity.

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?

Given the 3 parameters, nested objects, and no output schema, the description covers key behavioral aspects (immediate updates, undo history) and usage context (both modes, preference for plural tool). It does not explain return values, which would be helpful without an output schema, but overall it is quite complete for an agent to use effectively.

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 all parameters clearly. The description adds a bit of context around the namespace parameter (e.g., 'project:*' vs 'harness:*') but does not significantly enrich parameter meaning beyond what the schema provides. Baseline 3 is appropriate.

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 states a specific verb ('Execute') and resource ('a single command through the live WebSocket bridge'), and clearly distinguishes from the sibling tool 'execute_commands' by emphasizing singular execution. It also specifies the two namespaces it works with, making the tool's scope unambiguous.

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?

Explicitly provides an alternative and preference: 'PREFER execute_commands (plural) for batching — much faster.' This tells the agent when to use this tool vs. the sibling, and also clarifies that it works for both plan mode and assembly/harness mode, giving a clear situational context.

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