rzil_set_register

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

With no annotations provided, the description carries the behavioral disclosure burden. It discloses the important session prerequisite, which is genuinely useful beyond the schema. It does not describe what happens on invalid register names, whether the VM state is mutated in place, or what the return/error behavior looks like, but for a simple setter the prerequisite note provides meaningful context.

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 one compact sentence that front-loads the core action and then adds the critical requirement. There is no fluff, repetition, or unnecessary detail.

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 relatively simple setter tool, the description is nearly complete: it defines the action, names the VM context, and states the required session. Because there is no output schema, a note about expected return/error behavior would improve completeness, but the core information needed to invoke the tool correctly is present.

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 100%, so the schema already documents all three parameters with examples. The description adds no additional parameter semantics beyond what the schema provides, so the baseline of 3 is appropriate.

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 a specific action ('Set a register value') on a specific resource ('Rizin RzIL virtual machine'). This clearly distinguishes it from sibling tools like debug_set_register and esil_set_register by tying it to the RzIL VM, and from rzil_set_memory by targeting registers rather than memory.

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 gives a clear precondition ('Requires a persistent session from rzil_init'), which tells the agent when it is valid to call this tool. However, it does not explicitly explain when to choose rzil_set_register over similar siblings such as esil_set_register or debug_set_register; usage context is implied rather than stated.

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