device_config_block

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

The annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so safety behavior is well covered. The description adds the file_size>0 precondition and the reqType context, but it repeats 'Read-only' and does not describe return shape, block size, or error behavior. With rich annotations, this is adequate but not especially informative beyond structured fields.

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 two compact sentences and front-loads the core operation. The reqType detail and precondition are useful and there is no wasted prose.

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 tool with strong annotations, the description is sufficient to invoke the tool. However, there is no output schema, and the description does not explain what a block contains, its size, or the response shape, leaving interpretation of the return value under-specified.

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%, and both parameters are documented in the input schema: device_id comes from device_list and index is 0-based. The description adds no parameter-specific meaning beyond that schema. Baseline 3 is appropriate because the schema does the parameter work.

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 gives a specific verb and resource: fetch one board-config file block. It also ties the operation to the underlying GET_DEVICE_CONFIG reqType and distinguishes it from device_config_get by noting that it fetches one block after file_size>0. It does not explicitly distinguish itself from device_config_read, so it is strong but not fully sibling-differentiating.

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?

It provides a clear precondition: use after device_config_get reports file_size>0. That gives the agent actionable sequencing guidance. It does not explicitly state when not to use it or name an alternative such as device_config_read, so it falls short of full alternative routing.

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