b2_largest_files

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

Beyond the readOnlyHint=true annotation, the description discloses a live listing, bounded scan by max_scan and a time budget, and truncated=true. This materially shapes agent expectations about results being approximate on large buckets, and it explicitly states that file contents are never returned.

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?

Three sentences front-load the purpose, then explain the important scanning caveat and return contents. Every sentence earns its place with no filler or repetition.

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 helpfully states the return fields (name, size, upload time) and the truncated=true behavior. It doesn't discuss auth, error cases, or how it relates to b2_usage_growth, but for a read-only listing tool the essential information is present.

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?

The schema covers 100% of parameters with descriptions, and the tool description adds meaningful guidance for prefix and max_scan, explaining the full-listing requirement, truncation behavior, and subtree ranking. This adds value beyond the schema without needing to do more.

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 a specific action and resource ('List a bucket's largest objects by size') and clarifies that it returns metadata, never contents. It does not contrast itself with sibling tools like b2_usage_growth or b2_list_buckets, so an agent must infer 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?

Gives clear context with natural-language triggers ('largest files', 'what's taking up space') and instructs using a prefix for a complete subtree ranking. It does not explicitly name alternatives or when not to use this tool, though the 'never contents' caveat helps.

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