did_plot

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

Annotations indicate readOnlyHint=true (it creates a plot, which is read-like) and openWorldHint=false (likely a closed set of options). The description adds the key behavior of showing 'treatment effect with counterfactual' and implies it produces a diagram. It does not contradict annotations. However, it doesn't disclose details like whether the plot is displayed or saved, or how the counterfactual is computed.

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 a single sentence, concise and to the point. It front-loads the core purpose. However, it is so brief that it misses opportunities to add value beyond the schema, but it is not verbose or wasteful.

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 tool's moderate complexity (17 params, 4 required, but no nested objects beyond a colors array), the description provides only the basic purpose. The schema is rich, but the description doesn't guide the agent on what inputs are essential or typical (e.g., it doesn't emphasize that data_path, time, treat, y are required). With no output schema described in the prompt, the description should mention what the output looks like, which it doesn't.

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 input schema has 17 parameters with 100% coverage, each with descriptions (e.g., 'time' as 'Time period variable', 'treat' as 'Binary treatment group indicator'). The description adds no additional parameter semantics beyond the schema, but the schema is fully descriptive. Given high coverage, a baseline of 3 is appropriate, and the description's mention of 'counterfactual' aligns with the show_counterfactual parameter, slightly enhancing understanding.

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 it creates a 'Classic DID diagram showing treatment effect with counterfactual.' This is somewhat specific but could be confused with other DID plotting tools like did_summary_plot, event_study_plot, or bacon_plot. The description does not explicitly distinguish it from these siblings, and the name 'did_plot' is also somewhat generic.

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 no guidance on when to use this tool versus alternatives. It doesn't mention when to prefer this over other DID-related plotting tools, nor does it describe any prerequisites or typical workflows. It is clear that it plots a DID diagram, but there is no context on selection criteria or exclusions.

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