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

Annotations already declare destructiveHint=true, idempotentHint=false and readOnlyHint=false, so the safety profile is carried structurally. The description adds the concrete post-state (pieces become separate rows), but says nothing about consequences such as what happens to seat assignments, whether the operation can be reversed with group_segmented_rows, or why expectedUpdatedAt matters.

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 compact lines: effect first, trigger condition second, example third. Nothing is redundant and the most important information (what it undoes) is front-loaded.

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, non-idempotent mutation with no output schema, the definition covers the effect and the optimistic-concurrency parameter but not the blast radius (seats/rows affected, reversibility) or what the response contains. Adequate to invoke, thin for judging consequences.

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 groupId ("from get_chart") and expectedUpdatedAt ("meta.updatedAt from get_chart") are already fully documented. The inline example reinforces the call shape but adds no semantics beyond what the schema states.

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+resource (undo a joined/segmented row) and the resulting state ("its pieces show as separate rows again"), which clearly marks it as the inverse of group_segmented_rows among siblings. It stops short of naming the sibling tools it complements, but the operation is unmistakable.

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?

"Use when: rows were joined by mistake" gives an explicit trigger condition, which is more than most definitions in this set. It does not cover when NOT to use it (e.g. to split a normal row use split_row, or to merge seats use merge_rows), so the routing guidance is incomplete rather than absent.

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