get_module_package

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

With no annotations, the description carries the full burden; 'Fetches' implies a read-only operation and it usefully discloses the payload contents (manifest plus ESM sources), which is more than the schema says. However, it omits behavioral traits such as payload size, whether sources are truncated, or auth requirements for historical revisions.

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?

A single front-loaded sentence with the core action and payload named first and no filler. Every clause (complete manifest, ESM sources, active or historical) earns its place.

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?

There is no output schema, so the description must characterize the return value, and it does so by naming the manifest and ESM sources. For a two-parameter read tool with full schema coverage this is nearly sufficient; only the size/shape of the returned package is left implicit.

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%, so both module_id ('Reverse-domain Module id') and revision ('Optional historical revision') are already documented. The description's 'active or historical' phrasing loosely maps to the revision parameter but adds no format or default detail beyond the schema, making the baseline 3 correct.

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?

States a specific verb (Fetches) and resource (complete manifest and ESM sources for a Module revision), which is more precise than the sibling list_module_revisions or inspect_module. It never names an alternative or explicitly contrasts scope, so it stops short of full sibling differentiation.

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?

'active or historical Module revision' implies that supplying the revision parameter retrieves history and omitting it gets the current version, giving implicit usage context. There is no explicit when-to-use/when-not guidance and no routing to siblings such as get_rewrite_script_package or inspect_module.

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