MCP (Model Context Protocol) is an open standard from Anthropic that lets an AI assistant talk to an external tool through a typed, structured interface. Think of it as a USB connector for AI: one socket, many tools. The protocol is no longer Anthropic-only — Claude.ai, Claude Desktop, OpenAI and Google have all adopted it as the bridge between their models and third-party services.
TradeOnyx ships its own MCP server. Once you connect it to Claude.ai or Claude Desktop, the assistant can read your journal and, with your permission, write to it. No browser automation, no copy-paste, no "please paste this JSON into the form" workaround — Claude calls a typed tool, your TradeOnyx account changes, the next dashboard reload shows the result.
Three concrete use-cases that the integration unlocks today:
- End-of-day review without typing. "Claude, write a review for today's trades into my journal." Claude reads your closed trades via `trade_list`, summarises them, and posts the review through `journal_entry_upsert` under today's date.
- Log a trade while you're still in the position. "Claude, I just went long EURUSD at 1.10 — stop 1.095, target 1.115, tag it FOMO." Claude creates the trade via `trade_create` and attaches the tag through `tag_create`.
- Pull fresh broker data on demand. "Claude, fetch my latest Bybit fills." Claude calls `broker_sync_trigger`, the connector runs server-side, and the new trades show up in your Trades tab.
Who can use it (TRA-366). The MCP integration is now open to every tier — including Free accounts via a one-shot 7-day trial. The matrix:
- Free + 7-day trial — 34 logging tools, 30 tool calls per day, 7 days from activation.
- Pro (€29 / month) — 34 logging tools, 150 tool calls per day, no expiry.
- Pro Plus (€49 / month) — all 37 tools (logging + bulk analysis), 2,000 tool calls per day.
Free users activate the trial from Settings → Integrations or from the AI-co-pilot tile in the Welcome wizard. Activation is one-shot per account: the timestamp is stamped once and never reset, so the trial cannot be re-rolled by deleting and recreating the account.
What Claude can do (37 tools, scoped to your account). The set grew from 17 to 37 in the May-2026 expansion: full CRUD on playbooks and tags, attachments on trades and journal entries, planned-playbook scheduling, plus a read layer over every cached AI analysis the platform produces.
*Logging — Trades & Reviews (Free trial + Pro + Pro Plus):* - `trade_create` — log a new trade. - `trade_get` — one trade including notes and tags. - `trade_update` — edit your own annotations: stop, target, comment, external chart link, playbook assignment, target-RR, MFE and MAE prices. Broker-truth fields stay locked. - `trade_review_update` — write or update a trade's review note; pass `checklist_items` to snapshot the post-trade playbook checklist. - `trade_attachment_upload` / `trade_attachment_list` — attach and list images for a trade (base64 upload, JPEG/PNG/WebP, 5 MB cap).
*Logging — Journal:* - `journal_entry_get` — one journal entry by date. - `journal_entry_upsert` — create or replace the journal entry for a date; pass `plan_checklist_items` to snapshot the pre-market checklist. - `journal_attachment_upload` / `journal_attachment_list` — attach and list images for a journal entry. - `journal_planned_playbook_set` — pin a list of playbooks you plan to trade on a given date (idempotent). - `journal_planned_playbook_clear` — clear that list for a date (idempotent).
*Logging — Playbooks, tags, rules:* - `playbook_list`, `playbook_create`, `playbook_update`, `playbook_delete` — full CRUD; delete is a soft-delete (`is_active=false`) so historic trade-to-playbook links stay intact. - `tag_list`, `tag_create`, `tag_update`, `tag_delete` — full CRUD; delete refuses when the tag is still referenced by a trade. - `trading_rule_list`, `trading_rule_create`, `trading_rule_update` — manage trading rules.
*Logging — AI-read (cache-only):* - `briefing_get` — read the cached daily market briefing. - `news_analysis_get` / `news_analysis_list` — read cached news-AI analyses. - `econ_analysis_get` / `econ_analysis_list` — read cached economic-event analyses. - `market_heat_get` — read the cached market-heat snapshot. - `trade_ai_analysis_get` — read a cached trade AI analysis. - `pattern_narrative_get` / `pattern_recos_get` — read the cached weekly pattern narrative and recommendations. - `weekly_digest_get` — read the cached weekly AI digest.
*Logging — Sync:* - `broker_sync_trigger` — kick off a broker sync on an existing connection.
*Bulk analysis — Pro Plus only:* - `trade_list` — bulk list of closed and open trades with filters. - `journal_entry_list` — entries across a date range. - `stats_summary` — KPI overview (win-rate, expectancy, profit-factor) for a period.
Why split? The logging tools are how you put data in and read individual rows back. The bulk-analysis tools are how the AI reads aggregated state to write reviews and find patterns — that depth of insight is the Pro Plus value-add, alongside the on-server AI features themselves (pattern detection, weekly digest, news analysis).
What Claude deliberately cannot do. The integration is read-and-write for journal content, but a short list of surfaces stays UI-only on purpose:
- Account settings — email, password, 2FA, language, tier. A hallucinated `change_password` call is not an experience anyone wants.
- Broker API keys — connecting, rotating or removing credentials always happens in Settings, never through MCP. Keys are write-only in the database; even a compromised AI session cannot read them back.
- Trade deletions — destructive. If Claude misreads your request, an undo path through MCP would be a sharp edge. Deletions live in the Trades tab where a human click is required.
- Broker-truth fields on a trade — gross P/L, commission, swap, source, symbol, volume, open and close times, trade type. These are import-derived facts. `trade_update` accepts only your own annotations; any broker-truth field you pass is silently returned in `unchanged_fields` so the model gets clear feedback without overwriting reality.
- Triggering new AI analyses — the AI-read tools serve cached results only. They never call Anthropic from our server. To generate a fresh analysis, open the matching surface in the dashboard; the cost-controlled UI handles the live call.
- Admin functions — user management, feature flags, billing operations. Admin-only and AI-free, by policy.
The rule of thumb: anything that can damage the account if the model hallucinates or is prompt-injected stays behind the UI; anything that would spend new AI budget runs through the cost-controlled dashboard, not through MCP.
Two ways to connect — same MCP server underneath:
*Claude.ai Web (recommended for most people)* — Open Claude.ai → Settings → Connectors → Add custom connector. Paste the MCP URL (it's shown on the integrations card; today it's `https://app.tradeonyx.io/mcp`). Leave the OAuth fields empty — Claude.ai handles the sign-in flow itself: it'll open a TradeOnyx consent page in a new tab, you click Allow, and Claude.ai gets a scoped access-token back without you ever copying anything. No token to lose, no manual paste.
*Claude Desktop (and other clients without OAuth)* — Use a manual token. Open Settings → Integrations in TradeOnyx, click Generate token, copy it once (it's only shown once, then we store the hash). Paste it into Claude Desktop's developer settings alongside the same MCP URL.
Either way, the same 37 tools and the same revocation flow apply.
Setup in five steps:
1. Open Settings → Integrations and find the *Claude (MCP)* card. The card shows your tier and either a connect button or an upgrade hint. 2. Pick the path above — Web-OAuth (no manual token) or Desktop (generate one). 3. In Claude, add a custom MCP server with the URL from the TradeOnyx card. 4. Web path: click Allow on the consent screen. Desktop path: paste the token. Claude verifies the connection within a second; you see a green check on success. 5. Talk to Claude. "List my open trades." "Write a journal entry for today." "Add a new tag called *swing-breakout*." The first time Claude calls a write tool, it asks for your confirmation in the chat — you stay in the loop.
A practical first session. A workflow that tends to convince traders is the end-of-day review: ask Claude to fetch today's trades, group them by symbol, and write a one-paragraph review per group into your journal. Three minutes of conversation replaces twenty minutes of typing. The review lands in TradeOnyx exactly where it would have if you had written it yourself — same date, same field, same searchable history.
Revoking access. Open the integrations card and click *Disconnect* (or revoke the OAuth-issued token from the same list). The token is invalidated server-side immediately; any Claude session still holding it gets a 401 on the next tool call. Re-connecting later is a fresh token, never the old one.