set_direction

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

With no annotations, the description fully discloses behaviors: auto-acquires throttle, does not enforce stopping, returns direction as string independent of speed, is safe to call repeatedly (no-op), and handles exhibition mode explicitly.

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?

Well-structured with front-loaded purpose, clear sections for args, best practices, return value, and edge cases. Slightly verbose but every sentence adds value; could be trimmed slightly for extreme conciseness.

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 2 parameters, no output schema, and no annotations, the description is exceptionally complete: covers all behavioral aspects, edge cases (exhibition mode, redundant calls), return format, and ties to related tool (enter_exhibition_mode).

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%, but the description explains both parameters thoroughly: address (DCC, auto-acquire) and direction ('forward'/'reverse', case-insensitive, meaning relative to decoder). Adds crucial meaning beyond 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 description clearly states the tool sets a locomotive's direction to 'forward' or 'reverse' using a DCC address. It distinguishes from sibling tools like set_speed and stop by specifying the exact action and parameters.

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?

Provides explicit when-to-use and when-not-to-use: best practice to stop a moving loco first, warns of jolt/ignored command, explains behavior in exhibition mode (reverse refused), and suggests flipping current direction for 'turn around'.

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