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Evidence for your next connection.

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

Read-only probes

MCP server · Code & DevOps

useSignal

QR codes, JSON diff/format, hashes, JWT, cron, timestamps, placeholders, flowcharts, forms, regex.

Checks passed
14 / 22

1 failed · 7 not measured

Median response
472 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
12

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
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?
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 488 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name usesignal.

  • Pass
    Lists tools

    tools/list returned 12 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 472 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 486 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

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

    2 of 43 parameters have a description (5%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Not measured
    Website matches publisher

    This namespace is not a reverse domain, so the website comparison does not apply.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Pass
    Repo owner matches

    The GitHub repository owner matches the namespace login.

  • Pass
    Recently updated

    Updated 2026-10-03T05:56:09.17589Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using useSignal

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 usesignal https://www.usesignal.dev/mcp

Capabilities

Tools 12

usesignal_convert_timestamp

Convert a Unix timestamp (seconds or milliseconds) or an ISO 8601 date into ISO, UTC, epoch seconds/milliseconds, a relative time and the local time in a given time zone.

Discovered
usesignal_diff_json

Compare two JSON documents structurally and list every added, removed and changed value with its JSONPath. Numbers compare exactly. Arrays match by content by default, so an inserted item shows as one addition; use arrays:"position" to compare index by index.

Discovered
usesignal_encode_decode

Exact text transforms: Base64 encode/decode (UTF-8), URL encode/decode, decode a JWT header and payload with readable exp/iat/nbf dates (the signature is not verified), or hash text with MD5, SHA-1, SHA-256 and SHA-512. Use this instead of computing hashes or Base64 by hand.

Discovered
usesignal_explain_cron

Explain a standard 5-field cron expression (minute hour day-of-month month day-of-week) in plain English and list its next run times in a given time zone, handling daylight saving time.

Discovered
usesignal_flowchart

Turn JavaScript/TypeScript code, arrow steps or Mermaid-style arrows into a flowchart, returned as Mermaid source and an SVG diagram. Steps mode uses one flow per line: "Start -> Validate -> Save" and branches like "Validate -- No --> Show error".

Discovered
usesignal_format_json

Validate, pretty-print or minify JSON, optionally sorting keys. Invalid JSON reports the exact line and column; with repair (default on) it fixes common problems such as trailing commas, single quotes, comments and unquoted keys, and lists each fix.

Discovered
usesignal_generate_colors

Generate light and dark semantic color tokens from a six-digit hex brand color. Returns a shade scale, measured text contrast checks and CSS, JSON and Tailwind exports. This measures listed color pairs only, not whole-page accessibility. Call usesignal_open_workbench with the result input to preview.

Discovered
usesignal_generate_form

Generate an editable form from a JSON object. Returns nested field paths, JSON Schema, HTML, React JSX and config exports. Arrays and nulls use JSON textareas. Values are processed in memory; avoid secrets. To show an interactive preview, call usesignal_open_workbench with this result input.

Discovered
usesignal_generate_qr

Generate a scannable QR code for a link, text, Wi-Fi network, contact card (vCard), email, SMS, phone number, WhatsApp chat or UPI payment. Returns the encoded payload, an SVG file and a PNG preview image. values by type: url{url}; text{text}; wifi{ssid,password,security:WPA|WEP|nopass,hidden}; vcard{firstName,lastName,phone,email,org,title,website,address}; email{to,subject,body}; sms{phone,message}; phone{phone}; whatsapp{phone,message}; upi{vpa,name,amount,note}.

Discovered
usesignal_open_workbench

Show the editable useSignal UI. First call a useSignal data tool, then pass its returned input and matching tool name. Recomputes from validated inputs; no shared state.

Discovered
usesignal_placeholder_image

Create a placeholder image URL (served by usesignal.dev) plus HTML, Markdown and CSS snippets, for mockups, prototypes, seed data and layouts. Width and height up to 4000 px.

Discovered
usesignal_test_regex

Execute a JavaScript regular expression against text and expected match/non-match test cases. Returns indexed matches and capture groups. Flags use JavaScript semantics. Execution times out after 500ms. Call usesignal_open_workbench with result input to highlight matches.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected488 ms12
Connected455 ms12