3cx-api-patterns

# 3CX API Patterns ## Overview 3CX added a native MCP server built directly into the PBX, introduced in **3CX V20 Update 10** (announced July 30, 2026 as an **Alpha** release — 3CX's own release notes describe Update 10 Alpha as "intended for testing and evaluation only"). Treat everything in this plugin as based on that Alpha: exact tool names, the permissions reference, and behavior may all shift before 3CX ships Update 10 GA. This is a different project from the older third-party *SSIG-IT/3cx-mcp-server* on GitHub, a community-built MCP server that talks to 3CX's REST API rather than shipping inside the PBX. Do not mix the two up, and do not carry claims from the community project into this one — in particular, its "Enterprise/Enterprise Plus license required" claim is specific to that project and is **not** confirmed for 3CX's native MCP server. ## Anti-triggers - **The community *3cx-mcp-server* project** — different codebase, different tool surface, different auth model (its own API-key setup rather than per-PBX OAuth). Nothing in this plugin describes it, and nothing about it should be assumed here. - **A customer's "the phones are down" ticket** — that's ticket handling in the PSA, not a 3CX MCP call. Use `halopsa-tickets`, `connectwise-psa-tickets`, or `autotask-tickets` to work the ticket itself; come back to this plugin once you need the PBX-side facts. - **WYRE's Conduit vendor catalog** — 3CX has no catalog entry there and, structurally, cannot: Conduit's catalog vendors share one fixed endpoint per vendor, and every 3CX PBX is its own origin with its own authorization server. See *Connection & Authentication* below for the two ways this plugin actually reaches a PBX. ## Connection & Authentication ### Every PBX is its own endpoint Unlike a hosted SaaS MCP server, there is no single 3CX MCP URL. Each PBX exposes its own endpoint at its own FQDN, following the pattern: ``` https://yourpbx.3cx.eu/mcp ``` (or whatever FQDN that customer's PBX actually uses). Transport is Streamable HTTP. A skill, command, or agent in this plugin that needs to call a tool always does so against whichever PBX endpoint the current session is already connected to — nothing here can assume a fixed URL across customers. ### Admin-side setup (on the PBX) An admin enables the connection from inside that PBX's own console: 1. Sign into the 3CX Admin Console for the target PBX. 2. **Admin → Integrations → MCP Clients → Add MCP Client**. 3. 3CX displays the MCP Server URL for that PBX — copy it for the client-side step below. ### Client-side setup — direct connection (no gateway) For a technician working standalone in Claude Code, with no MSP gateway in front of it: ```bash claude mcp add --scope project --transport http 3CX "https://yourpbx.3cx.eu/mcp" claude ``` Then inside Claude: 1. Run `/mcp` and select the `3CX` server. 2. Choose **Authenticate**. Claude opens the 3CX authorization page in the browser. 3. Sign in, review the requested access, and select **Allow**. 4. Claude confirms the connection succeeded. The new connection also then shows up in that PBX's own **Admin → Integrations → MCP Clients** list — the authorization is visible and revocable from both sides. ### Client-side setup — through Conduit's BYO MCP feature An MSP already using WYRE's Conduit gateway for other vendors does not need a separate direct connection per PBX. Conduit has a generic **"Bring Your Own (BYO) MCP server"** feature (`/connect/byo`) built for exactly this shape — a vendor with no fixed shared endpoint. Paste the PBX's MCP URL from the admin step above into that form; Conduit then: 1. Discovers the PBX's own OAuth authorization server at runtime — RFC 9728 protected-resource metadata, then RFC 8414 authorization-server metadata. 2. Registers a client dynamically against that authorization server (RFC 7591 DCR). 3. Runs the normal authorization-code + PKCE flow, validating the callback's `iss` against the discovered issuer (RFC 9207) before persisting tokens. No 3CX-specific code exists in Conduit for this — the same generic BYO path handles any MCP server shaped this way. See *Tool permission tiers under Conduit BYO* below for how Conduit decides what an operator may call once connected, and this plugin's `GOVERNANCE.md` for the full picture. ## Permission Model Tool access is entirely inherited from the 3CX user account that approved the OAuth connection. Claude can do exactly what that account's 3CX role already permits inside 3CX — nothing more. There is no separate Claude-specific permission layer on the PBX side. One tool is restricted regardless of role: the `Query` tool (see the `pbx-admin` skill) is hard-restricted server-side to read-only SQL `SELECT` statements, no matter what the connecting account is otherwise allowed to do in 3CX. ## Discovering the Live Tool Surface 3CX's own "MCP Tools and Permissions Reference" documents these tools by human-readable label — find a contact by email, list active calls, drop a call, and so on — but does not publish the literal machine tool-name strings anywhere publicly accessible. The skills in this plugin describe the tool surface by capability for that reason, deliberately without inventing exact snake_case identifiers that cannot be verified against a real PBX. **Before calling a tool, confirm its real name and schema** by calling the standard MCP `tools/list` method against the connected PBX. This is also the only reliable way to know what changed between the Update 10 Alpha and any later release — the tool surface described here is a snapshot, not a guarantee. ## Tool permission tiers when the PBX is connected through the gateway Confirm the live grant in the gateway access editor after connecting. This skill does not describe how the gateway classifies tools. The read-only `Query` tool is enforced `SELECT`-only inside the PBX. Do not describe a workaround that reaches past that restriction, and do not assume a grant from the tool's name. ## Gotchas - **This is Alpha software.** Exact tool names, the permissions reference, and behavior can all change before 3CX ships Update 10 GA. Re-verify against `tools/list` rather than trusting a cached mental model, especially months after this was written. - **No shared URL.** Every other skill and command in this plugin assumes an already-connected PBX; there is nothing to hardcode across customers. - **Don't borrow tool names from the community *3cx-mcp-server* project** — it is a different codebase talking to a different API surface. ## Related Skills - [Directory & Contacts](../directory/SKILL.md) — contact and extension lookups - [Calls, Queues & Profiles](../calls-queues/SKILL.md) — live call/queue state and the write actions that change it - [PBX Admin & Diagnostics](../pbx-admin/SKILL.md) — system diagnostics, PBX inventory, and configuration writes