Similarweb

Similarweb names three: the API-only standalone package, Business, and Enterprise. Its MCP setup page lists a subscription with API access as the first prerequisite, and its Claude guide repeats that API access is included on Business and Enterprise plans and on the API standalone package. A platform-only Similarweb login without API access cannot connect the server.

Yes. Similarweb states the connector works with any API key as long as the key is active. That is worth knowing because the platform issues REST and Batch keys separately, under Settings then Account, and a team that only provisioned Batch keys does not need a second one. Keys must be toggled active or the client reports an invalid key.

Usually the domain string or its traffic volume. Similarweb lists four causes: a format error such as including www or https, uppercase characters, insufficient traffic to meet its minimum reporting threshold, and a domain too new to have accumulated data. Pass bare lowercase domains such as example.com. No credits are charged when no data is returned.

Yes. Similarweb states MCP uses the same data credits as standard API calls, drawn from the same allocation. Consumption scales with the volume returned rather than the number of calls, so one daily-granularity request over several countries and months can cost hundreds of credits. Usage appears in the platform under Account Settings then Data Credits Management.

Queries start failing rather than silently billing more. Similarweb states that once the allocation is exhausted for the billing period, MCP queries return an error, and its REST error table maps exhausted credits to HTTP 403 alongside an invalid key. Unused credits do not roll over; contact your account manager to raise the allocation.

Check the tool permissions in Claude first. Similarweb states that Similarweb tools set to Blocked under Tool permissions stop the connector returning data, and advises setting them to Always allow or Needs approval instead. If tools are permitted and queries still fail, confirm the API key is active and the subscription still includes API access.

Almost always a mismatched query rather than a data fault. Similarweb advises confirming that country, date range and web source — desktop, mobile web or total — match in both places. It also concedes that aggregation methodology differs slightly between the platform UI and the API, which accounts for minor residual variance.

Not live. Similarweb states daily data is released within 72 hours and monthly data by the 10th of the following month, and says explicitly that real-time data is unavailable because it measures actual user behaviour rather than live traffic. Its Claude guide adds that most datasets update monthly, with the prior month available by the end of the next.