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

Annotations already declare readOnlyHint=true, destructiveHint=false and closed-world scope, and the description reinforces that with 'It never changes the account'. Beyond that it adds non-annotation behavior: it returns the account's time zone and today's date, which the agent is told to trust over its own date sense, and it drives the 'IZeat ·' prefixed customer-facing statement. The trailing 'statement is the customer-facing IZeat message...' fragment is vague, but the time-zone/date directive is genuinely useful context.

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?

The purpose and the call-frequency rule are front-loaded, which is good, but the block then piles on response-formatting, time-zone, and profile-update instructions, and the trailing sentences ('statement is the customer-facing IZeat message...' and 'Account: Sam (review@izeat.app)') read as misplaced template/state text that obscures rather than informs.

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?

An output schema exists, so return values need not be restated, and annotations cover the safety profile; the description adds the usage cadence, the sibling hand-off, and the time-zone caveat that an agent needs to use the result correctly. The only shortfall is the garbled closing fragment, which leaves the response 'statement' contract less clear than it should be.

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 tool takes zero parameters, so per the baseline an empty description of inputs is expected and the schema has nothing to enumerate. The description correctly implies a no-argument call, shown by the example 'get_connected_account {}'; there is no parameter meaning to add.

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: 'Verifies the IZeat account connected to this conversation and reports its onboarding state.' It also differentiates itself from the nearby inspection tool by routing incomplete-onboarding cases to get_setup_step, so an agent can place it against get_profile and get_setup_step.

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 an explicit trigger ('once before the first IZeat operation in a conversation'), an explicit anti-trigger ('not before every meal'), and named alternatives ('use get_setup_step to determine the next step', 'store it with update_profile timezone'). This is close to a complete decision procedure.

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