diff --git a/docs/oauth-flow-schema-compilers-contract.md b/docs/oauth-flow-schema-compilers-contract.md
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+# OAuth flow ↔ Schema Compilers & Tooling contract
+
+## Purpose
+This document defines how OAuth/OIDC consent (provider granted scopes) should be mapped into Context’s category permission model so that Schema Compilers & Tooling can:
+- decide whether reads/writes are allowed for a given user+source
+- route sensitive field writes into user review
+- keep durable context aligned with Context’s “activity is not identity” and sensitivity rules
+
+## Key idea
+**OAuth grants scopes to a Tooling backend**. The backend must translate those scopes into **Context permissions** and then enforce field-level gating.
+
+Context category normalizers already emit:
+- `pending_approval_queue` (items requiring explicit confirmation)
+- `needs_review` (boolean)
+
+This repo provides the deterministic mapping contract logic:
+- `src/consent/oauth-consent-mapping.mjs`
+
+## OAuth model
+Use OIDC Authorization Code + PKCE (recommended).
+
+Backend should store:
+- access/refresh tokens (encrypted)
+- granted OAuth scopes
+- a `consent_version` (audit/version hash)
+- mapping decisions (scope sets derived from rules)
+
+## Mapping contract
+### Inputs
+`mapOauthGrantToContextPermissions(grant, mappingRules, contextPermissionsCatalog)`
+
+- `grant.granted_oauth_scopes`: scopes actually granted by the user at the IdP/provider
+- `mappingRules`: mapping from `provider_scope` → `context_scope`
+- `contextPermissionsCatalog`: metadata for Context scopes
+  - `scope` (e.g., `fitness-challenges:streaks`)
+  - `sensitivity` (low/medium/high)
+  - `default_granted`
+  - `first_write_requires_confirmation`
+
+### Output
+- `effective_context_permissions[]` where each item is:
+  - `allowed` (allowed by grant and/or default)
+  - `first_write_requires_confirmation`
+
+## Compiler write gating
+When a compiler job produces output fields that should be persisted, tooling should check:
+
+`canCompilerWriteWithConsent({ mappingOutput, required_context_scope, operation, is_first_write_for_that_scope })`
+
+Rules implemented:
+- **If permission is not allowed** → deny write
+- **If it is allowed but `first_write_requires_confirmation` and this is the first write** → allow but mark as **requires_review**
+- Reads are permitted when `allowed=true`
+
+## How this aligns with category normalizers
+Category normalizers (example: `src/categories/fitness-challenges.mjs`) already:
+- build `pending_approval_queue` items for sensitive fields
+- set `needs_review` when review is required
+
+Tooling should use the consent mapping to decide whether to:
+- execute writes immediately
+- or ensure review routing occurs for first writes of confirmation-gated permissions
+
+## Audit & revocation
+- Store `consent_version` alongside the grant.
+- If provider authorization is revoked, stop tooling ingestion for that source.
+- Prefer retaining only derived non-sensitive context, consistent with category-level sensitivity and durable preference rules.
+
diff --git a/src/consent/README.md b/src/consent/README.md
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+++ b/src/consent/README.md
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+OAuth→Consent contract (Schema Compilers & Tooling)
+
+This folder contains pure, deterministic logic used by Schema Compilers & Tooling backends.
+
+Goals
+- Convert provider/OAuth granted scopes into effective Context category permissions.
+- Provide backend-agnostic gating for whether compiler outputs should be routed to user review.
+
+Key modules
+- `oauth-consent-mapping.mjs`
+  - `mapOauthGrantToContextPermissions(grant, mappingRules, contextPermissionsCatalog)`
+  - `canCompilerWriteWithConsent({ mappingOutput, required_context_scope, operation, is_first_write_for_that_scope })`
+
+Integration expectation
+- Compiler jobs produce outputs like `pending_approval_queue` and `needs_review`.
+- This contract helps tooling decide when those review fields should be generated/triggered.
+
diff --git a/src/consent/oauth-consent-mapping.mjs b/src/consent/oauth-consent-mapping.mjs
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+++ b/src/consent/oauth-consent-mapping.mjs
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+/**
+ * OAuth→Consent mapping contract for Schema Compilers & Tooling.
+ *
+ * This module is intentionally pure (no IO): it defines deterministic
+ * mapping logic from provider/OAuth scopes to Context category permissions,
+ * plus field-level write gating semantics.
+ */
+
+/**
+ * @typedef {Object} ProviderToContextScopeRule
+ * @property {string} provider_scope OAuth scope granted by the IdP/provider.
+ * @property {string} context_scope Context scope defined by a category (e.g. "fitness-challenges:streaks").
+ */
+
+/**
+ * @typedef {Object} ContextPermission
+ * @property {string} scope Context scope id.
+ * @property {string} sensitivity "low"|"medium"|"high"|string
+ * @property {boolean} [default_granted]
+ * @property {boolean} [first_write_requires_confirmation]
+ */
+
+/**
+ * @typedef {Object} EffectiveContextPermission
+ * @property {string} scope
+ * @property {string} sensitivity
+ * @property {boolean} allowed
+ * @property {boolean} first_write_requires_confirmation
+ */
+
+/**
+ * @typedef {Object} OAuthGrantInput
+ * @property {string} user_id
+ * @property {string} source Source system connected by OAuth.
+ * @property {string} provider Provider name/id.
+ * @property {string[]} granted_oauth_scopes Scopes actually granted by the user.
+ * @property {string} consent_version A version/hash so tooling can audit mapping decisions.
+ */
+
+/**
+ * @typedef {Object} MappingOutput
+ * @property {string} consent_version
+ * @property {string} user_id
+ * @property {string} source
+ * @property {string} provider
+ * @property {EffectiveContextPermission[]} effective_context_permissions
+ */
+
+/**
+ * @param {OAuthGrantInput} grant
+ * @param {ProviderToContextScopeRule[]} mappingRules
+ * @param {ContextPermission[]} contextPermissionsCatalog
+ * @returns {MappingOutput}
+ */
+export function mapOauthGrantToContextPermissions(grant, mappingRules, contextPermissionsCatalog) {
+  const granted = new Set(Array.isArray(grant?.granted_oauth_scopes) ? grant.granted_oauth_scopes : [])
+
+  // Build a quick lookup of context permission metadata
+  const permissionByScope = new Map(
+    (Array.isArray(contextPermissionsCatalog) ? contextPermissionsCatalog : []).map((p) => [p.scope, p])
+  )
+
+  // Determine which Context scopes are granted based on OAuth scopes
+  const grantedContextScopes = new Set()
+  for (const rule of mappingRules || []) {
+    if (rule?.provider_scope && rule?.context_scope && granted.has(rule.provider_scope)) {
+      grantedContextScopes.add(rule.context_scope)
+    }
+  }
+
+  // Create an effective permissions list for all known context scopes.
+  const effective = []
+  for (const ctxScope of permissionByScopeKeys(permissionByScope)) {
+    const meta = permissionByScope.get(ctxScope)
+    const allowed = grantedContextScopes.has(ctxScope) || Boolean(meta?.default_granted)
+
+    effective.push({
+      scope: ctxScope,
+      sensitivity: meta?.sensitivity || "unknown",
+      allowed,
+      first_write_requires_confirmation: Boolean(meta?.first_write_requires_confirmation)
+    })
+  }
+
+  return {
+    consent_version: String(grant?.consent_version || ""),
+    user_id: String(grant?.user_id || ""),
+    source: String(grant?.source || ""),
+    provider: String(grant?.provider || ""),
+    effective_context_permissions: effective
+  }
+}
+
+/**
+ * Decide if a compiler output write should be routed to review for a given field.
+ *
+ * Compiler outputs in this repo already use the pattern:
+ * - `pending_approval_queue`: items with `requires_explicit_confirmation`
+ * - `needs_review`: boolean
+ *
+ * This helper provides a backend-agnostic check.
+ *
+ * @param {Object} params
+ * @param {MappingOutput} params.mappingOutput
+ * @param {string} params.required_context_scope
+ * @param {"read"|"write"} params.operation
+ * @param {boolean} params.is_first_write_for_that_scope
+ * @returns {{allowed: boolean, requires_review: boolean}}
+ */
+export function canCompilerWriteWithConsent({
+  mappingOutput,
+  required_context_scope,
+  operation,
+  is_first_write_for_that_scope
+}) {
+  const perms = mappingOutput?.effective_context_permissions || []
+  const perm = perms.find((p) => p.scope === required_context_scope)
+
+  if (!perm) {
+    return { allowed: false, requires_review: false }
+  }
+
+  if (operation === "write") {
+    if (!perm.allowed) return { allowed: false, requires_review: false }
+    if (perm.first_write_requires_confirmation && Boolean(is_first_write_for_that_scope)) {
+      return { allowed: true, requires_review: true }
+    }
+    return { allowed: true, requires_review: false }
+  }
+
+  // reads are less strict: if permission is allowed, allow.
+  if (operation === "read") {
+    if (!perm.allowed) return { allowed: false, requires_review: false }
+    return { allowed: true, requires_review: false }
+  }
+
+  return { allowed: false, requires_review: false }
+}
+
+function permissionByScopeKeys(map) {
+  return Array.from(map.keys())
+}
+
diff --git a/test/oauth-consent-mapping.test.mjs b/test/oauth-consent-mapping.test.mjs
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+import test from "node:test";
+import assert from "node:assert/strict";
+
+import {
+  mapOauthGrantToContextPermissions,
+  canCompilerWriteWithConsent
+} from "../src/consent/oauth-consent-mapping.mjs";
+
+test("mapOauthGrantToContextPermissions maps granted provider scopes -> effective context permissions", () => {
+  const grant = {
+    user_id: "u_1",
+    source: "StepApp",
+    provider: "steps-provider",
+    granted_oauth_scopes: ["provider:read_steps", "provider:write_streaks"],
+    consent_version: "v1"
+  };
+
+  const mappingRules = [
+    { provider_scope: "provider:read_steps", context_scope: "fitness-challenges:goals" },
+    { provider_scope: "provider:write_streaks", context_scope: "fitness-challenges:streaks" },
+    { provider_scope: "provider:write_preferences", context_scope: "fitness-challenges:preferences" }
+  ];
+
+  const catalog = [
+    { scope: "fitness-challenges:goals", sensitivity: "low", default_granted: true },
+    { scope: "fitness-challenges:preferences", sensitivity: "low", default_granted: true },
+    { scope: "fitness-challenges:streaks", sensitivity: "medium", default_granted: false, first_write_requires_confirmation: true }
+  ];
+
+  const out = mapOauthGrantToContextPermissions(grant, mappingRules, catalog);
+
+  const byScope = new Map(out.effective_context_permissions.map((p) => [p.scope, p]));
+
+  assert.equal(out.user_id, "u_1");
+  assert.equal(out.consent_version, "v1");
+
+  // default granted goals/preferences
+  assert.equal(byScope.get("fitness-challenges:goals").allowed, true);
+  assert.equal(byScope.get("fitness-challenges:preferences").allowed, true);
+
+  // granted streaks
+  assert.equal(byScope.get("fitness-challenges:streaks").allowed, true);
+  assert.equal(byScope.get("fitness-challenges:streaks").first_write_requires_confirmation, true);
+});
+
+test("canCompilerWriteWithConsent requires review on first write when permission requests confirmation", () => {
+  const mappingOutput = {
+    consent_version: "v1",
+    user_id: "u_1",
+    source: "StepApp",
+    provider: "steps-provider",
+    effective_context_permissions: [
+      {
+        scope: "fitness-challenges:streaks",
+        sensitivity: "medium",
+        allowed: true,
+        first_write_requires_confirmation: true
+      }
+    ]
+  };
+
+  const first = canCompilerWriteWithConsent({
+    mappingOutput,
+    required_context_scope: "fitness-challenges:streaks",
+    operation: "write",
+    is_first_write_for_that_scope: true
+  });
+
+  assert.deepEqual(first, { allowed: true, requires_review: true });
+
+  const subsequent = canCompilerWriteWithConsent({
+    mappingOutput,
+    required_context_scope: "fitness-challenges:streaks",
+    operation: "write",
+    is_first_write_for_that_scope: false
+  });
+
+  assert.deepEqual(subsequent, { allowed: true, requires_review: false });
+});
+
+test("canCompilerWriteWithConsent denies when permission is not allowed", () => {
+  const mappingOutput = {
+    effective_context_permissions: [
+      {
+        scope: "fitness-challenges:streaks",
+        sensitivity: "medium",
+        allowed: false,
+        first_write_requires_confirmation: true
+      }
+    ]
+  };
+
+  const out = canCompilerWriteWithConsent({
+    mappingOutput,
+    required_context_scope: "fitness-challenges:streaks",
+    operation: "write",
+    is_first_write_for_that_scope: true
+  });
+
+  assert.deepEqual(out, { allowed: false, requires_review: false });
+});
+