b2_update_bucket

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

Annotations already carry readOnlyHint=false and destructiveHint=true; the description adds value beyond them by naming the required capability (writeBuckets), enumerating the confirmation-gated cases (bucketType allPublic, fileLockEnabled false, defaultRetention.mode null, lifecycleRules with daysFromHidingToDeleting, replicationConfiguration updates), and flagging that delete-rule lifecycle updates are destructive in effect. No contradiction with the 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?

A single dense paragraph, front-loaded with purpose, followed by capability, precondition, alternative routing, and gated cases. Every clause carries distinct information, and nothing in the description repeats what the schema already documents.

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 an 11-parameter, confirmation-gated, destructive mutation tool with no output schema, the description covers capability requirements, precondition workflow, gated cases, and sibling differentiation — most of what an agent needs before invoking. The remaining gap is the response shape on success (e.g., updated bucket object and changed revision value), which would strengthen ifRevisionIs retry logic.

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 the baseline of 3 applies and the schema does the heavy lifting. The description adds only light operational context for two parameters (bucketId must be the exact ID, ifRevisionIs enables safer retries), which is useful but not new semantic meaning beyond the schema.

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 opens with a specific verb and resource — 'Update persistent settings on an existing B2 bucket' — and enumerates the scope (visibility, metadata, CORS, lifecycle, default encryption, replication, Object Lock, default retention). This cleanly distinguishes it from siblings like b2_create_bucket, b2_delete_bucket, and s3_put_bucket_lifecycle without requiring schema inspection.

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?

Provides an explicit precondition ('Use b2_list_buckets first to inspect the current bucketId/revision'), a safer retry pattern via ifRevisionIs, and a named alternative with a selection condition ('use s3_put_bucket_lifecycle only when you specifically need the S3 lifecycle API shape'). When-to-use, when-not-to-use, and alternatives are all spelled out.

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