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

Beyond the readOnlyHint annotation, the description discloses that generated templates 'rarely compiles without adaptation,' implying the output needs manual work. It also explains per-type behavior (find(), exist(), validateWrite(), initValue() for tables; stubs for public methods for classes) and states it uses 'REAL field names and method signatures from the knowledge base.' No contradiction with readOnlyHint since generating code without persisting is read-only.

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 dense but well-structured: trigger phrases and the WHEN condition are front-loaded, and the [!], REQUIRED, and per-type notes are scannable. Every sentence contributes (triggers, scope, caveat, required input, behavior, knowledge-base sourcing). It is on the longer side, but that length is justified for a code-generation tool with this complexity.

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 tool with no output schema and minimal annotations, the description covers when to use it, prerequisites, required inputs, per-object-type behavior, and a quality caveat. Minor gaps remain: it doesn't state the delivery format of the generated code (returned in-chat vs. file creation) and the fourth parameter's semantics are left entirely to the schema. These are modest omissions against an otherwise thorough definition.

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. The description adds genuine value beyond the schema by elevating testScenarios to REQUIRED (overriding the schema's optional flag), clarifying that each scenario becomes a concrete test method with arrange/act/assert, and specifying which generated methods apply per object type. This is meaningful semantic enrichment rather than repetition.

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 names a specific verb and resource: 'Generate X++ SysTest unit test code for a CUSTOM D365 F&O object.' It also carves out a distinct scope by insisting on custom/extension code only, which separates it from sibling generators like generate_xpp_template, generate_xpp_form, and generate_data_entity. An agent can tell what this tool does and what it is not for.

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 explicit when-to-use context (WHEN: developer needs unit tests), concrete trigger phrases, and a hard constraint ('[!] Only meaningful on custom/extension code') that acts as a when-not on standard code. It misses explicit naming of an alternative sibling tool to route to, so it falls just short of full 5-level guidance.

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