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

Read-only probes

MCP server · Other

Nostr Signer

By signer.frontiercrown.com

Approve Nostr signatures with your own browser signer without exposing a private key.

Source codeSearch & web data
Connect to Nostr Signer
Checks passed
12 / 22

2 failed · 8 not measured

Median response
519 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
17

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Outdated check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?
310
Publisher identityCan the publisher be traced to its source?
312

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 519 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name nostr-signer-chatgpt.

  • Pass
    Lists tools

    tools/list returned 17 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 519 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 519 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.

  • Fail
    Parameters documented

    8 of 29 parameters have a description (28%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Fail
    Website matches publisher

    The website host does not match 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 2026-09-11T05:59:17.916669Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using Nostr Signer

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 nostr-signer https://signer.frontiercrown.com/mcp

Capabilities

Tools 17

approve_grynvault_browser_handoff

Sign a short-lived, read-only Grynvault account handoff code so the browser tab that created it can receive its own dashboard. This does not create an invoice, publish a Nostr event, change settlement, or grant wallet custody.

Discovered
begin_nostrconnect_pairing

Advanced fallback: create a nostrconnect:// URI for the user to scan or open in a remote signer. Never accepts an nsec.

Discovered
connect_bunker

Connect a bunker:// URI only when the user knowingly supplied it. Prefer the local setup page so connection secrets are not placed in chat. Never accepts an nsec.

Discovered
create_grynvault_nip05_invoice

After separate explicit user confirmation, sign the prepared authorization and create exactly one pending 2,000-sat name@frontiercrown.com invoice. Does not pay, settle, activate, or prove identity.

Discovered
create_grynvault_supporter_invoice

After separate explicit user confirmation, sign the prepared authorization and create exactly one pending Grynvault supporter invoice. Does not pay it and never treats a redirect as settlement.

Discovered
disconnect_signer

Forget the in-memory signer session and all prepared events.

Discovered
get_grynvault_account_dashboard

Read the connected Nostr identity's Grynvault supporter, payment, and NIP-05 dashboard using a short-lived signed authorization. This does not create an invoice or change settlement.

Discovered
get_public_key

Return the public key exposed by the currently paired signer.

Discovered
get_setup_url

Return the loopback-only page used to connect a NIP-07 browser extension or an advanced NIP-46 signer.

Discovered
get_signer_status

Check whether a user-controlled NIP-07 or NIP-46 signer is connected.

Discovered
prepare_event

Validate and bind an exact unsigned Nostr event for user review. This does not sign or publish. Show the user every field before requesting a signature.

Discovered
prepare_grynvault_nip05_invoice

Check and normalize a name@frontiercrown.com identifier, then prepare its exact 2,000-sat invoice authorization. Does not sign, reserve the name, create, pay, or settle an invoice.

Discovered
prepare_grynvault_supporter_invoice

Prepare an exact, short-lived signed-authorization request for a one-time donation of 21 to 1,000,000 sats or the fixed 2,100-sat 30-day membership. Does not sign, create, pay, or settle an invoice.

Discovered
prepare_note

Prepare and bind an exact unsigned kind:1 note for user review. This does not sign or publish.

Discovered
publish_event

Publish a previously verified signed event to configured relays. Requires separate explicit user intent.

Discovered
query_events

Read a bounded set of verified public profile or note events from selected relays.

Discovered
sign_event

Ask the paired signer to approve and sign the exact event bound to a fresh intent. Requires explicit user intent and never publishes.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected519 ms17

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