Update Data Type

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

Adds substantial behavior beyond the annotations: descriptions are shared with existing readers, expected_description is a stale-read guard rather than an atomic compare-and-swap, only verified=true confirms readback, and blind retries are forbidden. Annotations cover the safety profile (destructive=true, idempotent=false) and the description layers the operational consequences on top.

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?

Front-loaded with the mutation scope, then the safety caveats, with no filler sentences. The phrasing is telegraphic in places ('Legacy annotations are not supported') which costs a little clarity, but nothing is padding.

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 a destructive mutation with an output schema, it covers everything an agent needs: authorization, field-replacement behavior, stale-read guarding, readback verification, and retry policy. Return-value detail is correctly left to the output schema.

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 100%, so the baseline is 3, but the description adds real meaning: 'Preserve unrelated description content' signals that description is a full replacement where partial edits destroy data, and 'expected_description rejects stale reads, not an atomic compare-and-swap' clarifies the concurrency guard's exact semantics.

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 precise verb and resource ('Update only name/description of an owned active Event/Metric type') along with the constraints (owned, active). The explicit exclusion 'No schema, record, or share changes' separates it cleanly from create_data_type, archive_data_type, restore_data_type and record_data without needing to name them.

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 operating context: user authorization required, read via get_data_catalog first, and reconcile rather than retry on uncertain writes. It does not explicitly contrast with sibling tools such as create_data_type or archive_data_type, so it stops short of full when/when-not routing.

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