Execute account custom action

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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=true, so 'WRITE:' merely restates structured data. The description adds no context about side effects, idempotency, validation behavior of the free-form field values, or what happens on an unknown action name — the traits an agent most needs for an open-world write.

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?

One short sentence, front-loaded with a mutation marker, so there is no waste. But the size borders on under-specification rather than genuine conciseness, and the 'WRITE:' label duplicates the readOnlyHint annotation.

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 open-world write tool with a free-form nested parameter object and no output schema, the description should explain field-value expectations, likely failure modes, and result shape. None of that is present, leaving the agent under-equipped for a non-trivial invocation.

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 both parameters are documented, giving a baseline of 3. However, the description adds nothing about the nested subscriptionAccount object, whose arbitrary key/value structure depends entirely on the chosen action — a point where description could have supplied real value.

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 and resource: running a named custom action on a subscription, and the 'WRITE:' prefix signals mutation. It does not distinguish itself from sibling tools such as get_account_custom_actions, which an agent might otherwise pair with it to discover valid action names.

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?

No guidance on when to use this versus get_account_custom_actions, nor any note that valid action names should be discovered first. The agent is left to infer the read-then-write workflow entirely.

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