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

Beyond the readOnly/openWorld annotations, it discloses real behavioral traits: the whole package is never returned (0x2 framework ~484 KB), there is no upstream paging so a truncated index carries no cursor, and repeated addresses arrive as `$n`/`@n` handles resolved by side tables. These are exactly the operational caveats annotations cannot convey.

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?

Five dense sentences that are largely front-loaded and each carries information (output shape, cap, escalation, size limit, handle resolution). The opening clause 'so a caller can pick what to inspect next' is slightly indirect, but there is no filler.

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?

With no output schema, the description still characterizes the return shape (index rows vs full module contents) and discloses the truncation/no-cursor limitation plus the maxModules-to-module-to-suiGetFunction escalation. For a read-only, three-parameter tool this is complete enough to invoke correctly.

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 only 33%, so the description carries most of the burden: it explains `module` (returns that module in full with every signature and datatype) and `maxModules` (raises the cap, ignored when `module` is given). It also touches handle resolution relevant to `package`, but does not spell out what the `package` value must be (package ID vs object ID), leaving a small gap.

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 precisely what the tool yields: an index of modules with names and function/datatype counts by default, or one module's full function and datatype declarations when `module` is passed. It differentiates from the sibling suiGetFunction ('suiGetFunction for a single signature') so an agent can route without opening a schema.

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 gives an explicit escalation path: use the default index, raise `maxModules` past the 50-row cap, pass `module` for full detail, and drop to suiGetFunction for a single signature. This is a clear when-to-use ladder with a named alternative, leaving nothing to inference.

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