# Tcx Brain > Author and manage TradingCodex Investment Brains. Use when the user asks to put principles or a Wiki insight into a Brain; create, inspect, revise, or validate a user-owned `investment-brain-*` source; or install, update, activate, deactivate, roll back, or remove a managed Brain. Natural-language source authoring is allowed, while lifecycle mutations require `$tcx-brain` on the first meaningful line of a root turn. - Skill: `monarchjuno/tcx-brain` (Agent Skill, multi-file: 3 files) - Install (CLI): `npx skillmds@latest add monarchjuno/tcx-brain` - Raw SKILL.md: https://api.skillmd.com/api/skills/monarchjuno/tcx-brain/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: monarchjuno (https://skillmd.com/u/monarchjuno) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/monarchjuno/tcx-brain --- # TCX Brain Manage the complete Investment Brain lifecycle through one user entrypoint. A Brain shapes Head Manager's inquiry and interpretation; it is not a Strategy, role roster, workflow, memory store, policy package, or execution extension. `$tcx-brain` manages Brains. It never selects one for analysis. A native analysis still requires one exact active `$investment-brain-*` id, either as a plain invocation or a Markdown link whose label and target match the projected workspace skill. Repeated references to the same id are deduplicated; distinct multiple ids fail closed. Read [bundle-contract.md](references/bundle-contract.md) before creating, revising, or deleting a user-owned source bundle. ## Action Model Keep the two managed layers distinct: - Source actions create, inspect, revise, validate, or explicitly delete a user-owned workspace-local bundle below `investment-brains/`. - Plugin actions list, inspect, install, update, activate, deactivate, roll back, or remove registry-managed immutable versions through the canonical `manage_investment_brain` MCP service. `remove` is the managed delete operation: it removes the Head Manager projection and marks the plugin removed while retaining immutable versions for run provenance. It does not delete a user-owned source directory. A source deletion is a separate, explicitly named action. ## Admission Natural-language requests may create or revise a user-owned source below `investment-brains/`, then run read-only validation. `list`, `inspect`, and `validate` require no lifecycle proof. Use the normal `trading-research` profile for both source and lifecycle work. Require `$tcx-brain` on the first meaningful line of a fresh root turn only for managed `install`, `update`, `activate`, `deactivate`, `rollback`, or `remove`. Do not combine it with `$tcx-build`, `$tcx-wiki`, `$tcx-strategy`, or an order marker. The marker grants only the matching current-turn lifecycle service call. Plan mode and subagents cannot perform managed lifecycle mutations. ## Source Procedure 1. For a new Brain, use the canonical `investment-brains/` source directory. Use a new lowercase hyphen-case `investment-brain-*` id and version `1.0.0` unless the user chose another valid initial version. 2. Revise or delete only a user-owned source directory explicitly identified by the user. Never edit or delete `.tradingcodex/investment-brains`, projected `.agents/skills/investment-brain-*`, a third-party package, an external source, or an upstream repository. Adapt third-party ideas only under a new user-owned id with a compatible license and original wording. 3. Use only material the user explicitly selected, including named Wiki pages, Decision Memory episodes, forecasts, postmortems, validated lessons, and contrary cases. Do not sweep memory or Wiki content or infer consent from relevance. Ask for the target Brain when no single user-owned source is unambiguous. 4. Require counterexamples and scope limits. Perform a privacy review that excludes private Investor Context, account or holding details, personal constraints, confidential sources, issuer-specific cases, and verbatim private prose. 5. Abstract the selected evidence into general hypotheses, inquiry priorities, interpretation principles, causal frames, scenarios, falsifiers, applicability limits, and abstention heuristics. Do not copy private cases, names, tickers, account facts, memory text, or factual Wiki prose into the bundle. 6. Before writing, state the abstraction, counterexamples, limitations, excluded private material, id, version, publisher, license, destination, and requested source action. An exact create or revise request with sufficient inputs already authorizes that reversible source change; do not add a redundant confirmation. Require a new explicit request for deletion or when a missing privacy/evidence choice would materially change the bundle. 7. Write only the strict source bundle described in the reference. Keep its content platform-neutral. It must not name roles, tools, models, sandboxes, workflow order, artifact paths, memory operations, policy, approval, broker, order, or execution authority. 8. For a source deletion, first state that installed immutable versions and historical provenance remain. Delete only the exact confirmed user-owned source files; do not translate source deletion into managed plugin removal or vice versa. 9. After create or revise, call the proof-free `manage_investment_brain` with `action="validate"` and `local_source=`. Changed content already represented by an installed version requires a version higher than every installed version. 10. Choose the minimum valid patch version greater than every installed version unless the user selected another higher version. Stop after any source create, revise, or delete action. Do not install, update, activate, remove, stage, commit, configure a remote, push, publish, or open a pull request in the same turn. A reviewed lifecycle action starts in a fresh explicit `$tcx-brain` turn. ## Managed Plugin Procedure 1. Identify exactly one explicit workspace-local source directory or public, credential-free HTTPS Git URL and ref. Do not infer a source or search a marketplace. Private, authenticated, SSH, file, or external local Git sources remain explicit user-terminal workflows. 2. Validate before install or update and inspect the returned id, version, source posture, content digest, and skill digest. 3. Install inactive first, then inspect the registry result. Activate only when the user explicitly requested that exact validated id and version. 4. Use only `manage_investment_brain`; its lifecycle mutations are proof-protected. Never edit registry, package, projection, generated index, or Head Manager config files directly. Select one exact action and only its matching fields: ```text action=list [active_only] action=inspect brain_id= action=validate local_source= action=validate git_source= [ref=] action=install local_source= action=install git_source= [ref=] action=update brain_id= [local_source=|git_source= ref=] action=activate|deactivate brain_id= action=rollback brain_id= [version=] action=remove brain_id= ``` Install always starts inactive. The MCP process owns service access; do not reopen the denied TradingCodex runtime or call its Python directly. 5. Update by publishing a higher immutable version. Never rewrite installed bytes under an existing version. Rollback selects an already-installed version; remove retains all installed versions for provenance. 6. Return the action, Brain id, selected version, status, validation posture, source posture, digests, projection posture, and exact next step. Do not expose credentials or absolute external local paths. ## Hard Stops - Do not mutate Decision Memory, Investor Context, a Strategy, or current evidence while managing a Brain. - Do not use `$tcx-build` as a wrapper or use the Brain grant for generic workspace maintenance. - Do not present a Brain as validated investment truth; current authenticated evidence can falsify it. - Do not stage, commit, configure a remote, push, publish, or open a pull request unless the user separately requests that Git or publication action. - Do not approve orders, grant broker authority, change policy, submit, cancel, or execute through this skill.