MCP server

Sipflow Official

dev.sipflow/sipflow

Checked 25 Oct 2026, 20:29 UTC · Connected to it and listed its tools

SIP/VoIP/telecom grounding for AI agents: vendor docs, RFCs, STIR/SHAKEN, traces, configs.

Website Source

At a glance

Type

MCP server

Publisher

sipflow.dev (verified by the MCP Registry)

Status

Working at last check

Tools

22

Token cost

About 12,653 tokens per request

Sets up in

Claude Code, Claude Desktop, Codex, Gemini CLI, Cursor, VS Code, Antigravity, ChatGPT, OpenAI API, Grok

Last checked

25 Oct 2026, 20:29 UTC

Connect it to your agent

Add to CursorAdd to VS CodeVS Code Insiders

Opens the app, which shows the server and asks you to confirm. For other apps, copy the setup below.

Claude Code

claude mcp add --transport http sipflow https://mcp.sipflow.dev/mcp

Claude Desktop

Settings → Connectors → Add custom connector, and paste the URL.

Codex (config.toml)

[mcp_servers.sipflow]
url = "https://mcp.sipflow.dev/mcp"

Gemini CLI

{"mcpServers":{"sipflow":{"httpUrl":"https://mcp.sipflow.dev/mcp"}}}

Cursor

{"mcpServers":{"sipflow":{"url":"https://mcp.sipflow.dev/mcp"}}}

VS Code

{"servers":{"sipflow":{"type":"http","url":"https://mcp.sipflow.dev/mcp"}}}

Antigravity

agy mcp add sipflow https://mcp.sipflow.dev/mcp

ChatGPT

Settings → Apps & Connectors → Advanced settings: turn on Developer mode, then Create a connector and paste the URL. Which plans can do this varies.

OpenAI API (Responses tools)

{"type":"mcp","server_label":"sipflow","server_url":"https://mcp.sipflow.dev/mcp","require_approval":"always"}

Grok (xAI API tools)

{"type":"mcp","server_label":"sipflow","server_url":"https://mcp.sipflow.dev/mcp"}

Tools

• compare_sdp_offer_answer ~391 tokens
  [cost: free (pure CPU, no network) | read-only] Diff a SIP/SDP offer and answer and surface the issues that actually break calls in practice: codec intersection per m-line, direction compatibility (sendrecv ↔ recvonly), DTLS setup-role conflicts (active+active / passive+passive), rtcp-mux / BUNDLE
• detect_sip_stack ~466 tokens
  [cost: free (pure CPU, no network) | read-only] Identify the SIP product behind a piece of input. Works on both: - a SIP trace (User-Agent / Server headers from PCAP/sngrep/syslog), and - a vendor config blob (kamailio.cfg, sip.conf, pjsip.conf, FreeSWITCH XML, opensips.cfg) detected via struct
• detect_sip_vendor_from_config ~294 tokens
  [cost: free (pure CPU, no network) | read-only] Heuristic-only sibling of `detect_sip_stack`, scoped to vendor configs. Returns the matched vendor slug, a confidence level, and the structural signals that fired (loadmodule syntax, route blocks, profile elements, etc.). Use this when the user asks
• diff_sip_messages ~519 tokens
  [cost: free (pure CPU, no network) | read-only, no persistence] Take two SIP messages (typically the same request observed at two adjacent hops - e.g. the INVITE leaving FreeSWITCH and the INVITE arriving at Kamailio) and surface a structured per-header diff: `added`, `removed`, `mutated` (with old
• dns_diagnose_sip_target ~753 tokens
  [cost: external_io (DNS via Cloudflare + Google; TLS handshake + a SIP OPTIONS keepalive to public targets when applicable) | read-only | rate-limited per IP: 10/min, 200/day] Walk DNS the same way a SIP UA does (RFC 3263 §4.1): NAPTR → SRV → A/AAAA. Given a SIP URI ("sip:example.com"), bare hostna
• fetch_sipflow_share ~699 tokens
  [cost: external_io (Mongo + S3 fetch on the Sipflow backend) | read-only, no persistence | rate limit: shared with the public share endpoint] Given a Sipflow share URL (https://sipflow.dev/share/<token>, or any sipflow.dev subdomain that serves /share/<token>), load the shared SIP trace AND any pri
• lint_sip_request ~472 tokens
  [cost: free (pure CPU, no network) | read-only, no persistence] Run RFC 3261 / RFC 3325 / RFC 8224 / RFC 8225 / CTIA BCID compliance checks on a single raw SIP request (typically an INVITE) and return a list of findings. Catches the failure modes that silently break carrier interop: - Two `From:
• lookup_response_code ~302 tokens
  [cost: free (pure CPU, no network) | read-only] Instant static lookup of a SIP response code (100-699). Returns name, RFC anchor, category, description, common operator-flavored causes, and known vendor-specific reason-phrase variants (e.g. OpenSIPS emits 484 'Invalid FROM' on From-header parse fai
• lookup_sip_header ~354 tokens
  [cost: free (pure CPU, no network) | read-only] Instant lookup of a SIP header by canonical or compact form (e.g. "Via" / "v", "Diversion", "P-Asserted-Identity", "Identity", "Session-Expires"). Returns canonical form, compact alias, RFC anchor, where it appears (request / response / both), cardina
• minimize_sip_trace ~483 tokens
  [cost: free (pure CPU, no network) | read-only, no persistence] Reduce a raw SIP trace to a compact form suitable for sending to an LLM. Preserves SDP bodies and routing/auth/dialog headers; prunes well-known noise (User-Agent, Server, Allow, Accept-*, Date, P-* informational, etc.). Expected inpu
• parse_sdp ~336 tokens
  [cost: free (pure CPU, no network) | read-only] Parse a Session Description Protocol body and return a structured view: origin, session, timing, per-media codecs (rtpmap + fmtp), direction, DTLS setup + fingerprint, ICE credentials + candidates, rtcp-mux, BUNDLE groups, fax-relay (`m=image udptl t3
• parse_sip_message ~397 tokens
  [cost: free (pure CPU, no network) | read-only, no persistence] Parse a single raw SIP message (request OR response) and return a structured view: start line (method/status), every header in order with line numbers, body, duplicate-header counts, and a list of structural flags the parser noticed (`
• render_sip_ladder ~1082 tokens
  [cost: free (pure CPU, no network) | read-only] Parse a raw SIP trace (PCAP-decoded text, sngrep export, syslog, or pasted INVITE/200 dialog) and emit a Mermaid `sequenceDiagram` block visualizing the call flow. Most chat hosts (Claude, ChatGPT, Cursor, GitHub) render Mermaid inline. Lane keying:
• review_sip_config ~700 tokens
  [cost: free (pure CPU, no network) | read-only] Use this when the user asks 'review my config' or attaches a kamailio.cfg, sip.conf, pjsip.conf, FreeSWITCH XML profile, opensips.cfg, `res_fax.conf` / `udptl.conf` / `spandsp.conf` (fax-relay tuning), or a SIP-shaped source file from a repo. This too
• search_sip_docs ~1096 tokens
  [cost: rag (one embed + one vector search) | read-only, network: outbound to embed model only] Vector search over Sipflow's curated VoIP knowledge base: vendor docs (Asterisk, FreeSWITCH, Kamailio, OpenSIPS, Twilio, Cisco, etc.), SIP/SDP/WebRTC RFCs, STIR/SHAKEN material (RFC 8224/8225/8226/8588/90
• sip_ladder_example ~531 tokens
  [cost: free (pure CPU, no network) | read-only] Return a hand-curated SIP scenario as a Mermaid `sequenceDiagram` plus a bullet list of step-by-step explanations with RFC references. Use this when the user asks 'show me what X looks like' and you don't have a real trace handy. Available scenarios:
• stir_attestation_explainer ~297 tokens
  [cost: free (pure CPU, no network) | read-only] Static explainer for STIR/SHAKEN: maps attestation levels (A / B / C per RFC 8588) to plain-English requirements + common scenarios, and SIP codes commonly emitted by signing/verification (428 / 436 / 437 / 438 / 608) to their RFC anchors and operator
• submit_sipflow_feedback ~1213 tokens
  [cost: write (single MongoDB row) | rate-limited per IP: 3/min, 20/day] Send the Sipflow team feedback when something doesn't work, a vendor or RFC isn't covered, or a tool produced a wrong/incomplete answer. Categories: - docs_gap: search_sip_docs returned nothing useful, vendor missing, coverag
• troubleshoot_response_code ~710 tokens
  [cost: rag (one embed + one vector search) | read-only, network: outbound to embed model only | rate-limited per IP] Like `lookup_response_code` but augmented: returns the static RFC entry PLUS the top vendor-specific RAG hits for the exact code (and any free-text context the user pasted). When the
• validate_e164_number ~320 tokens
  [cost: free (pure CPU, no network) | read-only] Parse a phone number, normalize to E.164, and classify it. International coverage is via libphonenumber-js (every country, line type when known). NANP numbers (CC=1) are additionally split into NPA (area code) / NXX (central office) / station, and tag
• validate_stir_shaken_identity ~700 tokens
  [cost: external_io (HTTPS fetch of the x5u cert) | read-only] Verify a SIP `Identity:` JWS (RFC 8224 / SHAKEN). Fetches the x5u certificate, parses it, verifies the ES256 signature against the cert's public key, and optionally validates the RCD icon hash (RFC 9795). The icon-hash check accepts both
• webrtc_sip_checklist ~538 tokens
  [cost: free (pure CPU, no network) | read-only] Return a curated checklist of WebRTC ↔ SIP requirements (WSS transport, ICE gathering, DTLS-SRTP fingerprint, rtcp-mux + BUNDLE, media relay / rtpengine, STUN/TURN, secure-context Origin allowlist, Opus codec, session-timer behavior across the bridge,

Browse

• Claude tools
• GitHub tools
• Website monitoring
• Domains and DNS
• Phone calls
• Notes and wikis

Related MCP servers

• Numbers Online — phone intelligence
  Read-only phone intelligence for AI voice agents — line type, risk, DNC, signed receipts.
• Telecom Truth
  US telecom availability and intelligence by address, with FCC provenance. Fiber-first.
• Apex Edge — x402-paid machine services
  x402-paid MCP tools: utils, audit screens, corpus search, inference. USDC Base+Solana.
• Whetstone
  Verifier-grounded AI promotion gates, disposable report cards, and signed PASS/HOLD/BLOCK receipts.
• Bernstein
  Verifies Bernstein run receipts and hash chains; lists the shipped presets and adapters. Read-only.
• PikaSim
  Anonymous eSIMs, phone numbers, and SMS codes in 190+ countries. Crypto-paid; agents self-onboard.
• FaultKey · CausalLayer
  Deterministic AI-liability attribution: signed, Bitcoin-anchored vendor/deployer/user fault split.
• Cannon VoIP AI Assistant
  Ask about Cannon VoIP pricing, plans, features, international rates, coverage, and FAQs.

Badge for your README

[![AptLynx](https://aptlynx.net/badge/dev.sipflow/sipflow.svg)](https://aptlynx.net/servers/dev.sipflow/sipflow)

Listing text is written by the maker; AptLynx lists tools and does not vouch for them. Find another tool · Browse by topic · For agents