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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds the return format (base64), which is useful behavioral context not present in annotations. It does not cover error handling, but the bar is lower given strong annotations.

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?

Two short, front-loaded sentences with no filler. Every word contributes to the core purpose and return format.

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 two well-documented parameters, safety annotations, and no output schema, the description covers the core purpose and mentions the base64 return. It omits edge-case behaviors (e.g., missing keys) but is sufficient for a simple read-only download tool.

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% for both bucket and key, so the description adds no parameter-specific meaning. The baseline 3 applies as the schema already does the heavy lifting.

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 uses a specific verb 'Download' with a clear resource 'object from storage', distinguishing it from sibling storage tools like upload or list. The note about base64 return further clarifies its unique purpose.

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 implies usage for retrieving object content but does not explicitly mention when to prefer this over scalix_storage_list or scalix_storage_upload, nor any exclusions or prerequisites. It is adequate for an obvious use case but lacks explicit guidance.

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