diff --git a/main.ts b/main.ts
index 0d0e856..30e0c1a 100644
--- a/main.ts
+++ b/main.ts
@@ -11,7 +11,6 @@ import type { AgentName, Payload } from "./external.ts";
 import { agentsManifest } from "./external.ts";
 import { ensureProgressCommentUpdated, reportProgress } from "./mcp/comment.ts";
 import { createMcpConfigs } from "./mcp/config.ts";
-import type { ReviewState } from "./mcp/review.ts";
 import { startMcpHttpServer } from "./mcp/server.ts";
 import { getModes, type Mode, modes } from "./modes.ts";
 import packageJson from "./package.json" with { type: "json" };
@@ -64,6 +63,7 @@ export async function main(inputs: Inputs): Promise<MainResult> {
 
     const partialCtx = await initializeContext(inputs, payload);
     const ctx = partialCtx as Context;
+    ctx.toolState = {};
     timer.checkpoint("initializeContext");
 
     await setupGit(ctx);
@@ -244,8 +244,17 @@ export interface Context {
   runId: string;
   jobId: string | undefined;
 
-  // iterative review state (set by start_review, cleared by submit_review)
-  reviewState: ReviewState | undefined;
+  // tool state - mutable scratchpad for tools
+  toolState: ToolState;
+}
+
+export interface ToolState {
+  prNumber?: number;
+  issueNumber?: number;
+  review?: {
+    id: number; // REST API database ID (for fix URLs)
+    nodeId: string; // GraphQL node ID (for mutations)
+  };
 }
 
 async function initializeContext(
@@ -263,7 +272,7 @@ async function initializeContext(
     | "prepResults"
     | "runId"
     | "jobId"
-    | "reviewState"
+    | "toolState"
   >
 > {
   log.info(`🐸 Running pullfrog/action@${packageJson.version}...`);
diff --git a/mcp/checkout.ts b/mcp/checkout.ts
index e23ec63..5ae0113 100644
--- a/mcp/checkout.ts
+++ b/mcp/checkout.ts
@@ -88,6 +88,9 @@ export function CheckoutPrTool(ctx: Context) {
         $("git", ["config", `branch.${headBranch}.pushRemote`, "origin"]);
       }
 
+      // set PR context
+      ctx.toolState.prNumber = pull_number;
+
       return {
         success: true,
         number: pr.data.number,
@@ -102,4 +105,3 @@ export function CheckoutPrTool(ctx: Context) {
     }),
   });
 }
-
diff --git a/mcp/comment.ts b/mcp/comment.ts
index 153db3f..3c6d927 100644
--- a/mcp/comment.ts
+++ b/mcp/comment.ts
@@ -204,7 +204,9 @@ export async function reportProgress(
   }
 
   // no existing comment - create one
-  const issueNumber = ctx.payload.event.issue_number;
+  // use fallback chain: dynamically set context > event payload
+  const issueNumber =
+    ctx.toolState.prNumber ?? ctx.toolState.issueNumber ?? ctx.payload.event.issue_number;
   if (issueNumber === undefined) {
     // cannot create comment without issue_number (e.g., workflow_dispatch events)
     return undefined;
diff --git a/mcp/issueComments.ts b/mcp/issueComments.ts
index 9678a4a..fa6c4d7 100644
--- a/mcp/issueComments.ts
+++ b/mcp/issueComments.ts
@@ -13,6 +13,9 @@ export function GetIssueCommentsTool(ctx: Context) {
       "Get all comments for a GitHub issue. Returns all comments including the issue body and all subsequent discussion comments.",
     parameters: GetIssueComments,
     execute: execute(ctx, async ({ issue_number }) => {
+      // set issue context
+      ctx.toolState.issueNumber = issue_number;
+
       const comments = await ctx.octokit.paginate(ctx.octokit.rest.issues.listComments, {
         owner: ctx.owner,
         repo: ctx.name,
diff --git a/mcp/issueEvents.ts b/mcp/issueEvents.ts
index dcbcdd1..9afc930 100644
--- a/mcp/issueEvents.ts
+++ b/mcp/issueEvents.ts
@@ -13,6 +13,9 @@ export function GetIssueEventsTool(ctx: Context) {
       "Get timeline events for a GitHub issue that aren't reflected in the current state. Returns cross-references to other issues/PRs and commit references. Note: current labels, assignees, state, and milestone are already available via get_issue.",
     parameters: GetIssueEvents,
     execute: execute(ctx, async ({ issue_number }) => {
+      // set issue context
+      ctx.toolState.issueNumber = issue_number;
+
       const events = await ctx.octokit.paginate(ctx.octokit.rest.issues.listEventsForTimeline, {
         owner: ctx.owner,
         repo: ctx.name,
diff --git a/mcp/issueInfo.ts b/mcp/issueInfo.ts
index 7535e57..656f990 100644
--- a/mcp/issueInfo.ts
+++ b/mcp/issueInfo.ts
@@ -20,6 +20,9 @@ export function IssueInfoTool(ctx: Context) {
 
       const data = issue.data;
 
+      // set issue context
+      ctx.toolState.issueNumber = issue_number;
+
       const hints: string[] = [];
       if (data.comments > 0) {
         hints.push("use get_issue_comments to retrieve all comments for this issue");
diff --git a/mcp/review.ts b/mcp/review.ts
index fa2fb00..e5d213b 100644
--- a/mcp/review.ts
+++ b/mcp/review.ts
@@ -84,15 +84,6 @@ type SubmitPullRequestReviewResponse = {
   };
 };
 
-// review state stored in ctx
-export interface ReviewState {
-  reviewId: string; // graphql node ID
-  reviewDatabaseId: number; // rest API ID
-  pullNumber: number;
-  scratchpadPath: string;
-  commentCount: number;
-}
-
 // start_review tool
 export const StartReview = type({
   pull_number: type.number.describe("The pull request number to review"),
@@ -106,9 +97,9 @@ export function StartReviewTool(ctx: Context) {
     parameters: StartReview,
     execute: execute(ctx, async ({ pull_number }) => {
       // check if review already started
-      if (ctx.reviewState) {
+      if (ctx.toolState.review) {
         throw new Error(
-          `Review session already started for PR #${ctx.reviewState.pullNumber}. Call submit_review first to finish it.`
+          `Review session already in progress. Call submit_review first to finish it.`
         );
       }
 
@@ -136,13 +127,11 @@ export function StartReviewTool(ctx: Context) {
       const scratchpadContent = `# Review ${scratchpadId}\n\n`;
       writeFileSync(scratchpadPath, scratchpadContent);
 
-      // store review state in ctx
-      ctx.reviewState = {
-        reviewId,
-        reviewDatabaseId,
-        pullNumber: pull_number,
-        scratchpadPath,
-        commentCount: 0,
+      // set PR context and review state
+      ctx.toolState.prNumber = pull_number;
+      ctx.toolState.review = {
+        nodeId: reviewId,
+        id: reviewDatabaseId,
       };
 
       return {
@@ -175,7 +164,7 @@ export function AddReviewCommentTool(ctx: Context) {
     parameters: AddReviewComment,
     execute: execute(ctx, async ({ path, line, body, side }) => {
       // check if review started
-      if (!ctx.reviewState) {
+      if (!ctx.toolState.review) {
         throw new Error("No review session started. Call start_review first.");
       }
 
@@ -183,7 +172,7 @@ export function AddReviewCommentTool(ctx: Context) {
       await ctx.octokit.graphql<AddPullRequestReviewThreadResponse>(
         ADD_PULL_REQUEST_REVIEW_THREAD,
         {
-          pullRequestReviewId: ctx.reviewState.reviewId,
+          pullRequestReviewId: ctx.toolState.review.nodeId,
           path,
           line,
           body,
@@ -191,11 +180,8 @@ export function AddReviewCommentTool(ctx: Context) {
         }
       );
 
-      ctx.reviewState.commentCount++;
-
       return {
         success: true,
-        commentCount: ctx.reviewState.commentCount,
         message: `Comment added to ${path}:${line}`,
       };
     }),
@@ -219,17 +205,19 @@ export function SubmitReviewTool(ctx: Context) {
     parameters: SubmitReview,
     execute: execute(ctx, async ({ body }) => {
       // check if review started
-      if (!ctx.reviewState) {
+      if (!ctx.toolState.review) {
         throw new Error("No review session started. Call start_review first.");
       }
+      if (ctx.toolState.prNumber === undefined) {
+        throw new Error("No PR context. Call checkout_pr or start_review first.");
+      }
 
-      const pullNumber = ctx.reviewState.pullNumber;
-      const reviewDatabaseId = ctx.reviewState.reviewDatabaseId;
+      const reviewId = ctx.toolState.review.id;
 
       // build quick links footer
       const apiUrl = process.env.API_URL || "https://pullfrog.com";
-      const fixAllUrl = `${apiUrl}/trigger/${ctx.owner}/${ctx.name}/${pullNumber}?action=fix&review_id=${reviewDatabaseId}`;
-      const fixApprovedUrl = `${apiUrl}/trigger/${ctx.owner}/${ctx.name}/${pullNumber}?action=fix-approved&review_id=${reviewDatabaseId}`;
+      const fixAllUrl = `${apiUrl}/trigger/${ctx.owner}/${ctx.name}/${ctx.toolState.prNumber}?action=fix&review_id=${reviewId}`;
+      const fixApprovedUrl = `${apiUrl}/trigger/${ctx.owner}/${ctx.name}/${ctx.toolState.prNumber}?action=fix-approved&review_id=${reviewId}`;
 
       const footer = buildPullfrogFooter({
         workflowRun: { owner: ctx.owner, repo: ctx.name, runId: ctx.runId, jobId: ctx.jobId },
@@ -242,17 +230,16 @@ export function SubmitReviewTool(ctx: Context) {
       const response = await ctx.octokit.graphql<SubmitPullRequestReviewResponse>(
         SUBMIT_PULL_REQUEST_REVIEW,
         {
-          pullRequestReviewId: ctx.reviewState.reviewId,
+          pullRequestReviewId: ctx.toolState.review.nodeId,
           body: bodyWithFooter,
           event: "COMMENT",
         }
       );
 
       const result = response.submitPullRequestReview.pullRequestReview;
-      const commentCount = ctx.reviewState.commentCount;
 
       // clear review state
-      ctx.reviewState = undefined;
+      delete ctx.toolState.review;
 
       // delete progress comment
       await deleteProgressComment(ctx);
@@ -262,7 +249,6 @@ export function SubmitReviewTool(ctx: Context) {
         reviewId: result.databaseId,
         html_url: result.url,
         state: result.state,
-        commentCount,
       };
     }),
   });
@@ -316,6 +302,9 @@ export function ReviewTool(ctx: Context) {
       "Only use 'body' for a 1-2 sentence summary with urgency and critical callouts.",
     parameters: Review,
     execute: execute(ctx, async ({ pull_number, body, commit_id, comments = [] }) => {
+      // set PR context
+      ctx.toolState.prNumber = pull_number;
+
       // get the PR to determine the head commit if commit_id not provided
       const pr = await ctx.octokit.rest.pulls.get({
         owner: ctx.owner,