plan_query

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

With readOnlyHint=true already present, the description adds a critical behavioral trait: 'Pure routing — no LLM call,' indicating deterministic, non-generative behavior. It also mentions 'ranked' output, but does not disclose behavior for unsupported intents or the exact output format, leaving some transparency gaps.

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?

Two concise sentences, front-loaded with the primary verb+resource and followed by key behavioral context. Zero 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 simple two-parameter read-only router, the description covers purpose, behavior, and supported intents. It lacks an explicit description of the return value format, but given the tool's simplicity and lack of output schema, this is a minor gap.

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 both parameters are already documented. The description adds value by enumerating the built-in intents (summarize, anomalies, compare, join, filter, trend, correlate), which helps the agent supply a valid `intent` value. No additional syntax is needed.

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 opens with a specific verb and resource: 'Map a natural-language intent into a ranked tool-call sequence for the given dataset.' This clearly distinguishes it from sibling execution tools (e.g., run_sql, aggregate) by positioning it as a pure planner/routing tool. It also lists supported intents, reinforcing its scope.

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 implies usage by stating it maps intent to a tool-call sequence, and the built-in intents list gives examples of when to use it. However, it does not explicitly compare against sibling tools or state when not to use it, so guidance is only implicit.

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