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Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Payments & trading

Polar MCP by usefulapi

By usefulapi.io Verified namespace

Products, customers, orders, subscriptions, benefits, revenue metrics and refunds.

WebsiteSource code
Connect to Polar MCP by usefulapi
Checks passed
14 / 22

0 failed · 8 not measured

Median response
59 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
26

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 59 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name polar-sh-mcp.

  • Pass
    Lists tools

    tools/list returned 26 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 59 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 59 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    105 of 105 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-11-10T23:33:33.208514Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using Polar MCP by usefulapi

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http polar-mcp-by-usefulapi https://polar-sh.usefulapi.io/mcp

Capabilities

Tools 26

polar_cancel_subscription

Cancel a subscription at the end of its current period. The customer keeps access until then. Polar: PATCH /v1/subscriptions/{id}.

Discovered
polar_create_checkout_link

Create a reusable checkout URL for one or more products — the link you put in a page or an email. Polar: POST /v1/checkout-links/.

Discovered
polar_create_refund

Refund an order, in full or in part. This moves real money back to the customer. Polar: POST /v1/refunds/.

Discovered
polar_get_customer

Fetch a single customer by Polar id. Polar: GET /v1/customers/{id}.

Discovered
polar_get_customer_state

Fetch everything about one customer in a single call — active subscriptions, granted benefits and entitlements. The best answer to 'what does this customer currently have?'. Polar: GET /v1/customers/{id}/state.

Discovered
polar_get_customer_state_by_external_id

Same as polar_get_customer_state, but looked up by YOUR external id rather than Polar's — the usual path when you hold your own user id. Polar: GET /v1/customers/external/{external_id}/state.

Discovered
polar_get_meter_quantities

Fetch the aggregated quantities a meter has recorded over a window — what usage-based billing will charge for. Polar: GET /v1/meters/{id}/quantities.

Discovered
polar_get_metrics

Fetch revenue and subscription metrics over a date range, bucketed by interval — orders, revenue, MRR, active subscriptions. Polar: GET /v1/metrics/.

Discovered
polar_get_order

Fetch a single order with its line items, discount and tax. Polar: GET /v1/orders/{id}.

Discovered
polar_get_product

Fetch a single product with its prices and attached benefits. Polar: GET /v1/products/{id}.

Discovered
polar_get_subscription

Fetch a single subscription with its product, price and period. Polar: GET /v1/subscriptions/{id}.

Discovered
polar_list_benefit_grants

List who has been granted one benefit, and whether the grant is still active. Polar: GET /v1/benefits/{id}/grants.

Discovered
polar_list_benefits

List benefits — the things a product grants, such as licence keys, file downloads or Discord roles. Polar: GET /v1/benefits/.

Discovered
polar_list_customers

List customers, optionally by email or a text query. Polar: GET /v1/customers/.

Discovered
polar_list_discounts

List discount codes and their redemption limits. Polar: GET /v1/discounts/.

Discovered
polar_list_events

List the raw usage events ingested for metering, filtered by customer, meter, name or time. Polar: GET /v1/events/.

Discovered
polar_list_license_keys

List issued licence keys and their status. Polar: GET /v1/license-keys/.

Discovered
polar_list_meters

List the usage meters that aggregate events into billable quantities. Polar: GET /v1/meters/.

Discovered
polar_list_orders

List orders, filtered by customer, product, subscription, status or a date window. Polar: GET /v1/orders/.

Discovered
polar_list_organizations

List the organisations the token can act for. Start here — most other tools take an organization_id. Polar: GET /v1/organizations/.

Discovered
polar_list_products

List products, optionally filtered by archived state, recurrence or a text query. Polar: GET /v1/products/.

Discovered
polar_list_refunds

List refunds, filtered by order, subscription, customer or success. Polar: GET /v1/refunds/.

Discovered
polar_list_subscriptions

List subscriptions, filtered by customer, product, status, active state or cancellation window. Polar: GET /v1/subscriptions/.

Discovered
polar_list_webhook_deliveries

List webhook delivery attempts with their HTTP results — the tool for 'why did my webhook not arrive?'. Polar: GET /v1/webhooks/deliveries.

Discovered
polar_list_webhook_endpoints

List the configured webhook endpoints and their subscribed events. Polar: GET /v1/webhooks/endpoints.

Discovered
polar_redeliver_webhook_event

Queue one webhook event for redelivery after your endpoint recovered. Polar: POST /v1/webhooks/events/{id}/redeliver.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected59 ms26

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