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

With no annotations, the description carries the full burden and does well: it discloses the free-preview branch for non-paying accounts, the plan default to pay-as-you-go, that a Stripe Checkout link is returned, and the security rule 'Never ask for card details.' It omits error/idempotency/permission behavior, but the disclosure of billing side effects is unusually rich.

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?

Purpose is front-loaded in the first clause, followed by the billing behavior and the follow-up call. Four clauses carry real information, though the payment explanation is dense and could be tightened.

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 2-param, no-annotation, no-output-schema mutation tool, the description covers purpose, the free-vs-paid branch, the returned checkout link, and the required next step. It lacks guidance on failure modes or repeat calls, minor gaps given the otherwise thorough coverage.

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 meaning beyond the schema by explaining that 'plan' defaults to pay-as-you-go when omitted and ties it implicitly to list_plans. This is genuine added value over the schema's bare 'Optional plan name or ID' text.

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 first sentence states a specific verb and resource ('Creates a space for one capture'), and the resource 'space' is clearly distinct from sibling resources like tours. An agent can identify the operation without opening the schema.

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?

The description gives strong conditional workflow guidance: non-paying accounts get a free private preview, otherwise the tool returns a Stripe Checkout link and the caller should then invoke wait_for_payment, a named sibling. It does not, however, differentiate from create_tour or explain edge cases such as re-invocation.

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