mb_read

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

With no annotations, the description must disclose behavioral traits. It only states 'Read memory bytes', implying a read-only operation, but does not clarify if the call is synchronous, if it requires an existing connection, how errors are handled, or if it has side effects. The lack of detail leaves significant ambiguity.

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 extremely concise at 5 words, with no superfluous information. It is front-loaded with the core action. However, it may be too brief to be fully useful, sacrificing completeness for conciseness.

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 tool has an output schema (not shown but present), the description does not need to detail return values. However, it lacks context about prerequisites (e.g., connection required), the specific PLC memory area accessed, or how it relates to sibling tools. For a tool in a complex domain, this is incomplete.

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%: both 'start' and 'size' are clearly described in the input schema as 'Start byte offset' and 'Number of bytes to read'. The description adds no additional semantic meaning beyond the schema, meeting the baseline for well-documented parameters.

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 'Read memory bytes from PLC.' clearly states the action (read) and resource (memory bytes from PLC). However, it does not differentiate from sibling read tools like ab_read or ct_read, which likely target different protocols or memory areas. The name 'mb_read' suggests a specific context (e.g., Modbus), but this is not explained.

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?

No guidance on when to use this tool versus alternatives (e.g., when to use mb_read vs ab_read). No mention of prerequisites (e.g., must be connected to a PLC) or exclusions. The description provides no usage context.

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