gb_encode_register_value

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

With no annotations, the description carries the full burden. It describes what the tool returns but does not explicitly state that it is a read-only computation, nor does it disclose error behavior or constraints on field values. For a pure function this is acceptable but not exhaustive.

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 concise—two sentences—with the primary purpose front-loaded and the output specifics following immediately. Every word contributes to understanding the tool's function.

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 absence of an output schema, the description usefully lists the returned components (byte, breakdown, shift expression, assembly). It does not elaborate on edge cases or the exact format of these components, but for a tool with a nested object parameter and no output schema, the provided context is largely sufficient.

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 schema already covers both parameters with descriptions (register name/address, fields object with value types). The tool description adds no additional semantic detail beyond the schema, so it does not exceed the baseline for high schema coverage.

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: 'Build the byte that produces a desired register configuration.' It also names the output artifacts (byte, binary breakdown, shift expression, RGBDS-style assembly), making the purpose specific and distinguishable from the sibling decode tool.

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 explicitly identifies this as the inverse of `gb_decode_register_value`, giving clear guidance on when to use it (for encoding) versus decoding. However, it does not mention other related lookup or list tools, leaving some comparison to the agent.

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