plan_advance

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

The description discloses multiple behavioral traits beyond the annotations, including the mandatory evidence/reason requirements, automatic promotion of the next pending step, updates to next_move, and the 'cannot skip without reason' constraint. This gives a comprehensive view of the tool's side effects and validation rules.

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 consists of two concise, front-loaded sentences. Every sentence contributes meaningful information: one states the core action and prerequisites, the other explains the automatic behavior and enforcement. There is no redundancy or filler.

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, this description sufficiently covers purpose, conditions, and side effects. It handles the main use cases and explains the state transition. Minor gaps exist, such as behavior when there is no pending next step, but these are not critical for primary usage.

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 100%, so the baseline is 3. The description adds value by clarifying the conditional dependency between action and evidence/reason, which is not fully captured in the schema. This helps the agent understand which fields are required in which scenarios.

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's function: 'Complete or skip the current plan step.' This specificity distinguishes it from sibling tools like plan_add (which adds steps) and plan_read (which reads plans). The verb-resource pairing is precise.

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 description provides clear context for when to use 'complete' vs 'skip' by requiring evidence or reason respectively. It also explains the automatic promotion of the next step and the continuity enforcement. While it doesn't explicitly name alternative tools, the guidance is sufficient to infer appropriate usage.

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