Control Debug Session

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

Goes well beyond the annotations (readOnly=false, destructive=false, idempotent=false): it discloses the failure mode without a session, the prerequisite IDE/project state, and critically that the call returns as soon as the IDE accepts the command without reporting the new line or variable values. That last point prevents an agent from expecting state back and re-polling, which is exactly the kind of context structured fields cannot convey.

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?

Front-loads the purpose, then actions, then prerequisites, then return behavior in a logical order with no filler. The inline action glosses partially duplicate the schema description, costing a little tightness, but each sentence carries information an agent needs.

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?

No output schema exists, and the description compensates by explicitly describing what the call does and does not return. With a single required parameter fully documented and a clear failure condition, an agent has everything needed to invoke this correctly.

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, but the description adds real semantics by glossing each action ("step_over" executes current line, "step_into" steps into a method call, "step_out" exits the current method, "resume" continues, "pause" halts). This resolves any ambiguity about what the terse enum values mean in practice.

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?

States a specific verb and resource ("Controls the Xojo debug session") and immediately enumerates the five concrete actions, so an agent knows exactly which operation family this is. It is clearly distinguishable from siblings like run_project or stop_project, which manipulate the session lifecycle rather than stepping through it.

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 states the precondition: an active debug session started with run_project, and that the call fails without one. It also states the IDE must be running with the project open. The only gap is that it never names stop_project as the way to end a session, but the when-to-use condition is unambiguous.

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