diff --git a/__tests__/api/task-offers.test.ts b/__tests__/api/task-offers.test.ts
new file mode 100644
index 0000000..6fa1c1b
--- /dev/null
+++ b/__tests__/api/task-offers.test.ts
@@ -0,0 +1,131 @@
+import { describe, it, expect, beforeEach, afterEach } from "vitest"
+import { GET as listOffers, POST as createOffer } from "@/app/api/task-offers/route"
+import { DELETE as cancelOffer, GET as getOffer } from "@/app/api/task-offers/[id]/route"
+import { resetTaskOffersForTests } from "@/lib/task-market/offers"
+
+async function mockRequest(url: string, options?: RequestInit): Promise<Request> {
+  return new Request(url, options)
+}
+
+async function mockContext(params: Record<string, string>) {
+  return { params: Promise.resolve(params) } as any
+}
+
+describe("Task offer API", () => {
+  beforeEach(() => {
+    resetTaskOffersForTests()
+  })
+
+  afterEach(() => {
+    resetTaskOffersForTests()
+  })
+
+  it("creates and lists open offers by required capability", async () => {
+    const deadline = Math.floor(Date.now() / 1000) + 3600
+    const createReq = await mockRequest("http://localhost:3000/api/task-offers", {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({
+        postedBy: "agent-alpha",
+        requiredCapability: "run-inference",
+        payload: { prompt: "summarize this" },
+        reward: "0.05 XLM",
+        deadline,
+      }),
+    })
+
+    const createRes = await createOffer(createReq)
+    const createData = await createRes.json()
+    expect(createRes.status).toBe(201)
+    expect(createData.ok).toBe(true)
+    expect(createData.offerId).toMatch(/^off_/)
+    expect(createData.escrowTx).toMatch(/^escrow_/)
+    expect(createData.offer.reward).toEqual({ amount: "0.05", asset: "XLM" })
+
+    const listReq = await mockRequest("http://localhost:3000/api/task-offers?cap=run-inference")
+    const listRes = await listOffers(listReq)
+    const listData = await listRes.json()
+    expect(listRes.status).toBe(200)
+    expect(listData.ok).toBe(true)
+    expect(listData.offers).toHaveLength(1)
+    expect(listData.offers[0].offerId).toBe(createData.offerId)
+  })
+
+  it("returns a single offer by id", async () => {
+    const createRes = await createOffer(await mockRequest("http://localhost:3000/api/task-offers", {
+      method: "POST",
+      body: JSON.stringify({
+        postedBy: "agent-beta",
+        requiredCapability: "classify",
+        reward: { amount: "1.5", asset: "USDC" },
+        deadline: Math.floor(Date.now() / 1000) + 3600,
+      }),
+    }))
+    const { offerId } = await createRes.json()
+
+    const response = await getOffer(
+      await mockRequest(`http://localhost:3000/api/task-offers/${offerId}`),
+      await mockContext({ id: offerId }),
+    )
+    const data = await response.json()
+    expect(response.status).toBe(200)
+    expect(data.ok).toBe(true)
+    expect(data.offer.postedBy).toBe("agent-beta")
+  })
+
+  it("lets only the poster cancel an open offer", async () => {
+    const createRes = await createOffer(await mockRequest("http://localhost:3000/api/task-offers", {
+      method: "POST",
+      body: JSON.stringify({
+        postedBy: "agent-owner",
+        requiredCapability: "translate",
+        reward: "0.25 XLM",
+        deadline: Math.floor(Date.now() / 1000) + 3600,
+      }),
+    }))
+    const { offerId } = await createRes.json()
+
+    const forbidden = await cancelOffer(
+      await mockRequest(`http://localhost:3000/api/task-offers/${offerId}?agentId=other-agent`, { method: "DELETE" }),
+      await mockContext({ id: offerId }),
+    )
+    expect(forbidden.status).toBe(403)
+
+    const response = await cancelOffer(
+      await mockRequest(`http://localhost:3000/api/task-offers/${offerId}`, {
+        method: "DELETE",
+        headers: { "x-agent-id": "agent-owner" },
+      }),
+      await mockContext({ id: offerId }),
+    )
+    const data = await response.json()
+    expect(response.status).toBe(200)
+    expect(data.ok).toBe(true)
+    expect(data.offer.status).toBe("cancelled")
+    expect(data.refundTx).toMatch(/^refund_/)
+  })
+
+  it("rejects invalid rewards and expired deadlines", async () => {
+    const invalidReward = await createOffer(await mockRequest("http://localhost:3000/api/task-offers", {
+      method: "POST",
+      body: JSON.stringify({
+        postedBy: "agent-alpha",
+        requiredCapability: "run-inference",
+        reward: "free",
+        deadline: Math.floor(Date.now() / 1000) + 3600,
+      }),
+    }))
+    expect(invalidReward.status).toBe(400)
+
+    const expiredDeadline = await createOffer(await mockRequest("http://localhost:3000/api/task-offers", {
+      method: "POST",
+      body: JSON.stringify({
+        postedBy: "agent-alpha",
+        requiredCapability: "run-inference",
+        reward: "0.05 XLM",
+        deadline: Math.floor(Date.now() / 1000) - 1,
+      }),
+    }))
+    expect(expiredDeadline.status).toBe(400)
+  })
+})
diff --git a/app/api/task-offers/[id]/route.ts b/app/api/task-offers/[id]/route.ts
new file mode 100644
index 0000000..6063f79
--- /dev/null
+++ b/app/api/task-offers/[id]/route.ts
@@ -0,0 +1,55 @@
+import { NextResponse } from "next/server"
+import { cancelTaskOffer, getTaskOffer } from "@/lib/task-market/offers"
+
+export const dynamic = "force-dynamic"
+export const runtime = "nodejs"
+
+type RouteContext = {
+  params: Promise<{ id: string }>
+}
+
+function actorFromRequest(req: Request): string {
+  const url = new URL(req.url)
+  return String(req.headers.get("x-agent-id") ?? url.searchParams.get("agentId") ?? "").trim()
+}
+
+export async function GET(_req: Request, context: RouteContext) {
+  const { id } = await context.params
+  const offer = getTaskOffer(decodeURIComponent(id))
+  if (!offer) {
+    return NextResponse.json(
+      { ok: false, error: "Task offer not found" },
+      { status: 404, headers: { "Cache-Control": "no-store" } },
+    )
+  }
+
+  return NextResponse.json({ ok: true, offer }, { headers: { "Cache-Control": "no-store" } })
+}
+
+export async function DELETE(req: Request, context: RouteContext) {
+  const { id } = await context.params
+  const actorId = actorFromRequest(req)
+  if (!actorId) {
+    return NextResponse.json(
+      { ok: false, error: "agentId is required" },
+      { status: 400, headers: { "Cache-Control": "no-store" } },
+    )
+  }
+
+  try {
+    const offer = cancelTaskOffer(decodeURIComponent(id), actorId)
+    return NextResponse.json({ ok: true, offer, refundTx: offer.refundTx }, { headers: { "Cache-Control": "no-store" } })
+  } catch (error) {
+    const message = error instanceof Error ? error.message : "Failed to cancel task offer"
+    let status = 400
+    if (message.includes("not found")) {
+      status = 404
+    } else if (message.includes("Only the poster")) {
+      status = 403
+    }
+    return NextResponse.json(
+      { ok: false, error: message },
+      { status, headers: { "Cache-Control": "no-store" } },
+    )
+  }
+}
diff --git a/app/api/task-offers/route.ts b/app/api/task-offers/route.ts
new file mode 100644
index 0000000..2b4acc1
--- /dev/null
+++ b/app/api/task-offers/route.ts
@@ -0,0 +1,42 @@
+import { NextResponse } from "next/server"
+import { createTaskOffer, listTaskOffers } from "@/lib/task-market/offers"
+
+export const dynamic = "force-dynamic"
+export const runtime = "nodejs"
+
+export async function GET(req: Request) {
+  const url = new URL(req.url)
+  const requiredCapability = url.searchParams.get("cap")?.trim() || undefined
+  const includeExpired = url.searchParams.get("includeExpired") === "1"
+
+  return NextResponse.json(
+    {
+      ok: true,
+      offers: listTaskOffers({ requiredCapability, includeExpired }),
+    },
+    { headers: { "Cache-Control": "no-store" } },
+  )
+}
+
+export async function POST(req: Request) {
+  try {
+    const body = await req.json()
+    const offer = createTaskOffer({
+      postedBy: String(body.postedBy ?? req.headers.get("x-agent-id") ?? ""),
+      requiredCapability: String(body.requiredCapability ?? ""),
+      payload: body.payload && typeof body.payload === "object" ? body.payload : {},
+      reward: body.reward,
+      deadline: Number(body.deadline),
+    })
+
+    return NextResponse.json(
+      { ok: true, offerId: offer.offerId, escrowTx: offer.escrowTx, offer },
+      { status: 201, headers: { "Cache-Control": "no-store" } },
+    )
+  } catch (error) {
+    return NextResponse.json(
+      { ok: false, error: error instanceof Error ? error.message : "Failed to create task offer" },
+      { status: 400, headers: { "Cache-Control": "no-store" } },
+    )
+  }
+}
diff --git a/lib/task-market/offers.ts b/lib/task-market/offers.ts
new file mode 100644
index 0000000..bed1531
--- /dev/null
+++ b/lib/task-market/offers.ts
@@ -0,0 +1,162 @@
+export type TaskOfferAsset = "XLM" | "USDC"
+export type TaskOfferStatus = "open" | "claimed" | "delivered" | "accepted" | "disputed" | "expired" | "cancelled"
+
+export interface TaskOfferReward {
+  amount: string
+  asset: TaskOfferAsset
+}
+
+export interface TaskOffer {
+  offerId: string
+  postedBy: string
+  requiredCapability: string
+  payload: unknown
+  reward: TaskOfferReward
+  deadline: number
+  status: TaskOfferStatus
+  escrowTx: string
+  refundTx?: string
+  createdAt: string
+  updatedAt: string
+}
+
+export interface CreateTaskOfferInput {
+  postedBy: string
+  requiredCapability: string
+  payload?: unknown
+  reward: string | Partial<TaskOfferReward>
+  deadline: number
+}
+
+interface TaskOfferState {
+  offers: Map<string, TaskOffer>
+  sequence: number
+}
+
+const globalState = globalThis as typeof globalThis & {
+  __openStellarTaskOffers__?: TaskOfferState
+}
+
+const state: TaskOfferState = globalState.__openStellarTaskOffers__ ?? {
+  offers: new Map(),
+  sequence: 0,
+}
+
+globalState.__openStellarTaskOffers__ ??= state
+
+function assertNonEmpty(value: unknown, field: string): string {
+  const text = typeof value === "string" ? value.trim() : ""
+  if (!text) throw new Error(`${field} is required`)
+  return text
+}
+
+function nextOfferId(): string {
+  state.sequence += 1
+  return `off_${Date.now().toString(36)}_${state.sequence.toString(36)}`
+}
+
+function isTaskOfferAsset(value: unknown): value is TaskOfferAsset {
+  return value === "XLM" || value === "USDC"
+}
+
+function normalizeReward(reward: string | Partial<TaskOfferReward>): TaskOfferReward {
+  if (typeof reward === "string") {
+    const match = /^(\d+(?:\.\d+)?)\s+(XLM|USDC)$/i.exec(reward.trim())
+    if (!match) throw new Error("reward must be formatted like '0.05 XLM'")
+    const amount = match[1]
+    const asset = match[2].toUpperCase()
+    if (Number(amount) <= 0) throw new Error("reward amount must be > 0")
+    if (!isTaskOfferAsset(asset)) throw new Error("reward asset must be XLM or USDC")
+    return { amount, asset }
+  }
+
+  if (!reward || typeof reward !== "object") {
+    throw new Error("reward is required")
+  }
+
+  const amount = String(reward.amount ?? "").trim()
+  const asset = String(reward.asset ?? "").trim().toUpperCase()
+  if (!amount || Number(amount) <= 0 || !Number.isFinite(Number(amount))) {
+    throw new Error("reward amount must be > 0")
+  }
+  if (!isTaskOfferAsset(asset)) throw new Error("reward asset must be XLM or USDC")
+  return { amount, asset }
+}
+
+function normalizeDeadline(deadline: number): number {
+  const value = Number(deadline)
+  if (!Number.isFinite(value)) throw new Error("deadline must be a unix timestamp")
+  const timestamp = value > 10_000_000_000 ? Math.floor(value / 1000) : Math.floor(value)
+  if (timestamp <= Math.floor(Date.now() / 1000)) throw new Error("deadline must be in the future")
+  return timestamp
+}
+
+function escrowHash(prefix: "escrow" | "refund", offerId: string): string {
+  return `${prefix}_${offerId}_${crypto.randomUUID()}`
+}
+
+function refreshOfferExpiry(offer: TaskOffer): TaskOffer {
+  if (offer.status !== "open" || offer.deadline > Math.floor(Date.now() / 1000)) {
+    return offer
+  }
+  const expired = {
+    ...offer,
+    status: "expired" as const,
+    refundTx: offer.refundTx ?? escrowHash("refund", offer.offerId),
+    updatedAt: new Date().toISOString(),
+  }
+  state.offers.set(offer.offerId, expired)
+  return expired
+}
+
+export function resetTaskOffersForTests(): void {
+  state.offers.clear()
+  state.sequence = 0
+}
+
+export function createTaskOffer(input: CreateTaskOfferInput): TaskOffer {
+  const now = new Date().toISOString()
+  const offerId = nextOfferId()
+  const offer: TaskOffer = {
+    offerId,
+    postedBy: assertNonEmpty(input.postedBy, "postedBy"),
+    requiredCapability: assertNonEmpty(input.requiredCapability, "requiredCapability"),
+    payload: input.payload ?? {},
+    reward: normalizeReward(input.reward),
+    deadline: normalizeDeadline(input.deadline),
+    status: "open",
+    escrowTx: escrowHash("escrow", offerId),
+    createdAt: now,
+    updatedAt: now,
+  }
+  state.offers.set(offer.offerId, offer)
+  return offer
+}
+
+export function getTaskOffer(offerId: string): TaskOffer | null {
+  const offer = state.offers.get(offerId)
+  return offer ? refreshOfferExpiry(offer) : null
+}
+
+export function listTaskOffers(filters: { requiredCapability?: string; includeExpired?: boolean } = {}): TaskOffer[] {
+  return [...state.offers.values()]
+    .map(refreshOfferExpiry)
+    .filter((offer) => filters.includeExpired || offer.status === "open")
+    .filter((offer) => !filters.requiredCapability || offer.requiredCapability === filters.requiredCapability)
+    .sort((a, b) => a.deadline - b.deadline || a.offerId.localeCompare(b.offerId))
+}
+
+export function cancelTaskOffer(offerId: string, actorId: string): TaskOffer {
+  const offer = getTaskOffer(offerId)
+  if (!offer) throw new Error("Task offer not found")
+  if (offer.postedBy !== actorId) throw new Error("Only the poster can cancel this offer")
+  if (offer.status !== "open") throw new Error("Only open offers can be cancelled")
+  const cancelled = {
+    ...offer,
+    status: "cancelled" as const,
+    refundTx: offer.refundTx ?? escrowHash("refund", offer.offerId),
+    updatedAt: new Date().toISOString(),
+  }
+  state.offers.set(offerId, cancelled)
+  return cancelled
+}