diff --git a/packages/capabilities/package.json b/packages/capabilities/package.json
index 8cb3085d..a02822f6 100644
--- a/packages/capabilities/package.json
+++ b/packages/capabilities/package.json
@@ -109,6 +109,7 @@
     "uint8arrays": "^5.0.3"
   },
   "devDependencies": {
+    "@ipld/dag-ucan": "^3.4.0",
     "@storacha/eslint-config": "workspace:^",
     "@types/assert": "^1.5.6",
     "@types/mocha": "^10.0.0",
diff --git a/packages/capabilities/src/blob.js b/packages/capabilities/src/blob.js
index ea113aab..59269696 100644
--- a/packages/capabilities/src/blob.js
+++ b/packages/capabilities/src/blob.js
@@ -15,15 +15,7 @@
  */
 import { capability, Schema, Link, ok } from '@ucanto/validator'
 import { content } from './space/blob.js'
-import {
-  equalBlob,
-  equalWith,
-  SpaceDID,
-  and,
-  equal,
-  checkLink,
-  Await,
-} from './utils.js'
+import { equalBlob, equalWith, and, equal, checkLink, Await } from './utils.js'
 
 /**
  * Capability can only be delegated (but not invoked) allowing audience to
@@ -50,7 +42,7 @@ export const allocate = capability({
     /** Link to the add blob task that initiated the allocation. */
     cause: Schema.link({ version: 1 }),
     /** DID of the user space where the allocation takes place. */
-    space: SpaceDID,
+    space: Schema.bytes(),
   }),
   derives: (claimed, delegated) =>
     and(equalWith(claimed, delegated)) ||
@@ -73,7 +65,7 @@ export const accept = capability({
     /** Blob to accept. */
     blob: content,
     /** DID of the user space where allocation took place. */
-    space: SpaceDID,
+    space: Schema.bytes(),
     /** This task is blocked on `http/put` receipt available */
     _put: Await,
   }),
diff --git a/packages/capabilities/test/capabilities/blob.test.js b/packages/capabilities/test/capabilities/blob.test.js
index 1cdcb1f3..26cdbb3b 100644
--- a/packages/capabilities/test/capabilities/blob.test.js
+++ b/packages/capabilities/test/capabilities/blob.test.js
@@ -1,6 +1,7 @@
 import assert from 'assert'
 import { access } from '@ucanto/validator'
 import { ed25519, Verifier } from '@ucanto/principal'
+import * as DID from '@ipld/dag-ucan/did'
 import * as Blob from '../../src/blob.js'
 import * as Capability from '../../src/top.js'
 import {
@@ -44,7 +45,7 @@ describe('blob capabilities', function () {
           digest: car.cid.multihash.bytes,
           size: car.bytes.length,
         },
-        space: space.did(),
+        space: DID.parse(space.did()),
         cause: await createCborCid({ now: Date.now() }),
       },
       proofs: [await top()],
@@ -74,7 +75,7 @@ describe('blob capabilities', function () {
           digest: car.cid.multihash.bytes,
           size: car.bytes.length,
         },
-        space: space.did(),
+        space: DID.parse(space.did()),
         cause: await createCborCid({ now: Date.now() }),
       },
       proofs: [await blob()],
@@ -111,7 +112,7 @@ describe('blob capabilities', function () {
           digest: car.cid.multihash.bytes,
           size: car.bytes.length,
         },
-        space: space.did(),
+        space: DID.parse(space.did()),
         cause: await createCborCid({ now: Date.now() }),
       },
       proofs: [blob],
@@ -138,7 +139,7 @@ describe('blob capabilities', function () {
       audience: bob,
       with: account.did(),
       nb: {
-        space: space0.did(),
+        space: DID.parse(space0.did()),
       },
       proofs: [await top()],
     })
@@ -152,7 +153,7 @@ describe('blob capabilities', function () {
           digest: car.cid.multihash.bytes,
           size: car.bytes.length,
         },
-        space: space1.did(),
+        space: DID.parse(space1.did()),
         cause: await createCborCid({ now: Date.now() }),
       },
       proofs: [blob],
@@ -181,7 +182,7 @@ describe('blob capabilities', function () {
           digest: car.cid.multihash.bytes,
           size: car.bytes.length,
         },
-        space: space.did(),
+        space: DID.parse(space.did()),
         _put: {
           'ucan/await': ['.out.ok', await createCborCid('receipt')],
         },
@@ -213,7 +214,7 @@ describe('blob capabilities', function () {
           digest: car.cid.multihash.bytes,
           size: car.bytes.length,
         },
-        space: space.did(),
+        space: DID.parse(space.did()),
         _put: {
           'ucan/await': ['.out.ok', await createCborCid('receipt')],
         },
@@ -252,7 +253,7 @@ describe('blob capabilities', function () {
           digest: car.cid.multihash.bytes,
           size: car.bytes.length,
         },
-        space: space.did(),
+        space: DID.parse(space.did()),
         _put: {
           'ucan/await': ['.out.ok', await createCborCid('receipt')],
         },
@@ -281,7 +282,7 @@ describe('blob capabilities', function () {
       audience: bob,
       with: account.did(),
       nb: {
-        space: space0.did(),
+        space: DID.parse(space0.did()),
       },
       proofs: [await top()],
     })
@@ -295,7 +296,7 @@ describe('blob capabilities', function () {
           digest: car.cid.multihash.bytes,
           size: car.bytes.length,
         },
-        space: space1.did(),
+        space: DID.parse(space1.did()),
         _put: {
           'ucan/await': ['.out.ok', await createCborCid('receipt')],
         },
diff --git a/packages/upload-api/src/blob/accept.js b/packages/upload-api/src/blob/accept.js
index 8f907ff0..b41d5b85 100644
--- a/packages/upload-api/src/blob/accept.js
+++ b/packages/upload-api/src/blob/accept.js
@@ -3,6 +3,8 @@ import { Message, Invocation } from '@ucanto/core'
 import * as Transport from '@ucanto/transport/car'
 import * as API from '../types.js'
 import * as HTTP from '@storacha/capabilities/http'
+import * as DID from '@ipld/dag-ucan/did'
+import * as Digest from 'multiformats/hashes/digest'
 import { AgentMessage } from '../lib.js'
 
 /**
@@ -95,7 +97,14 @@ export const poll = async (context, receipt) => {
     return messageWrite
   }
 
-  const register = await context.registry.register(allocate.nb)
+  const register = await context.registry.register({
+    space: /** @type {API.SpaceDID} */ (DID.decode(allocate.nb.space).did()),
+    cause: allocate.nb.cause,
+    blob: {
+      digest: Digest.decode(allocate.nb.blob.digest),
+      size: allocate.nb.blob.size,
+    },
+  })
   if (register.error) {
     // it's ok if there's already a registration of this blob in this space
     if (register.error.name !== 'EntryExists') {
diff --git a/packages/upload-api/src/blob/add.js b/packages/upload-api/src/blob/add.js
index 5d431ef0..5dc3a2cd 100644
--- a/packages/upload-api/src/blob/add.js
+++ b/packages/upload-api/src/blob/add.js
@@ -6,6 +6,7 @@ import * as Blob from '@storacha/capabilities/blob'
 import * as SpaceBlob from '@storacha/capabilities/space/blob'
 import * as HTTP from '@storacha/capabilities/http'
 import * as Digest from 'multiformats/hashes/digest'
+import * as DID from '@ipld/dag-ucan/did'
 import * as API from '../types.js'
 import { allocate as spaceAllocate } from '../space-allocate.js'
 import { createConcludeInvocation } from '../ucan/conclude.js'
@@ -126,7 +127,7 @@ async function allocate({ context, blob, space, cause }) {
         digest: blob.digest,
         size: blob.size,
       },
-      space,
+      space: DID.parse(space),
       cause,
     },
   })
@@ -271,7 +272,7 @@ async function accept({ context, provider, blob, space, delivery }) {
     with: provider.did(),
     nb: {
       blob,
-      space,
+      space: DID.parse(space),
       _put: { 'ucan/await': ['.out.ok', delivery.task.link()] },
     },
   })
diff --git a/packages/upload-api/src/blob/get.js b/packages/upload-api/src/blob/get.js
index 3f3fa998..72d70a05 100644
--- a/packages/upload-api/src/blob/get.js
+++ b/packages/upload-api/src/blob/get.js
@@ -13,9 +13,20 @@ export function blobGetProvider(context) {
     const digest = Digest.decode(capability.nb.digest)
     const space = Server.DID.parse(capability.with).did()
     const res = await context.registry.find(space, digest)
-    if (res.error && res.error.name === 'EntryNotFound') {
-      return Server.error(new BlobNotFound(digest))
+    if (res.error) {
+      if (res.error.name === 'EntryNotFound') {
+        return Server.error(new BlobNotFound(digest))
+      }
+      return res
     }
-    return res
+
+    return Server.ok({
+      blob: {
+        digest: res.ok.blob.digest.bytes,
+        size: res.ok.blob.size,
+      },
+      cause: res.ok.cause,
+      insertedAt: res.ok.insertedAt.toISOString(),
+    })
   })
 }
diff --git a/packages/upload-api/src/blob/list.js b/packages/upload-api/src/blob/list.js
index 75614864..5ebaf48d 100644
--- a/packages/upload-api/src/blob/list.js
+++ b/packages/upload-api/src/blob/list.js
@@ -10,6 +10,20 @@ export function blobListProvider(context) {
   return Server.provide(SpaceBlob.list, async ({ capability }) => {
     const space = capability.with
     const { cursor, size } = capability.nb
-    return await context.registry.entries(space, { size, cursor })
+    const result = await context.registry.entries(space, { size, cursor })
+    if (result.error) {
+      return result
+    }
+    return Server.ok({
+      ...result.ok,
+      results: result.ok.results.map((r) => ({
+        blob: {
+          digest: r.blob.digest.bytes,
+          size: r.blob.size,
+        },
+        cause: r.cause,
+        insertedAt: r.insertedAt.toISOString(),
+      })),
+    })
   })
 }
diff --git a/packages/upload-api/src/types.ts b/packages/upload-api/src/types.ts
index 375409eb..18101f19 100644
--- a/packages/upload-api/src/types.ts
+++ b/packages/upload-api/src/types.ts
@@ -161,7 +161,11 @@ import { RevocationsStorage } from './types/revocations.js'
 export * from '@storacha/capabilities/types'
 export * from '@ucanto/interface'
 
-export type { ProvisionsStorage, Provision, Subscription } from './types/provisions.js'
+export type {
+  ProvisionsStorage,
+  Provision,
+  Subscription,
+} from './types/provisions.js'
 export type {
   DelegationsStorage,
   Query as DelegationsStorageQuery,
diff --git a/packages/upload-api/src/types/blob.ts b/packages/upload-api/src/types/blob.ts
index b584ba05..ee97d251 100644
--- a/packages/upload-api/src/types/blob.ts
+++ b/packages/upload-api/src/types/blob.ts
@@ -14,7 +14,6 @@ import type {
 } from '@ucanto/interface'
 import {
   Multihash,
-  BlobItem as Entry,
   BlobAllocate,
   BlobAccept,
   BlobAllocateSuccess,
@@ -24,7 +23,16 @@ import { MultihashDigest } from 'multiformats'
 import { ListResponse, SpaceDID } from '../types.js'
 import { Storage } from './storage.js'
 
-export type { Entry }
+export interface Blob {
+  digest: MultihashDigest
+  size: number
+}
+
+export interface Entry {
+  blob: Blob
+  cause: Link
+  insertedAt: Date
+}
 
 /** Indicates an entry was not found that matches the passed details. */
 export interface EntryNotFound extends Failure {
@@ -71,7 +79,7 @@ export interface BlobModel {
 export interface RegistrationData {
   space: SpaceDID
   cause: Link
-  blob: BlobModel
+  blob: Blob
 }
 
 export interface BlobService {
diff --git a/packages/upload-api/test/external-service/index.js b/packages/upload-api/test/external-service/index.js
index 6dedf184..98c1e274 100644
--- a/packages/upload-api/test/external-service/index.js
+++ b/packages/upload-api/test/external-service/index.js
@@ -5,7 +5,13 @@ import { BrowserStorageNode, StorageNode } from './storage-node.js'
 import * as BlobRetriever from './blob-retriever.js'
 import * as RoutingService from './router.js'
 
-export { ClaimsService, BrowserStorageNode, StorageNode, BlobRetriever, RoutingService }
+export {
+  ClaimsService,
+  BrowserStorageNode,
+  StorageNode,
+  BlobRetriever,
+  RoutingService,
+}
 
 /**
  * @param {object} config
diff --git a/packages/upload-api/test/external-service/storage-node.js b/packages/upload-api/test/external-service/storage-node.js
index 77cb74a0..6c08b4d7 100644
--- a/packages/upload-api/test/external-service/storage-node.js
+++ b/packages/upload-api/test/external-service/storage-node.js
@@ -10,7 +10,10 @@ import { ed25519 } from '@ucanto/principal'
 import { CAR, HTTP } from '@ucanto/transport'
 import * as Server from '@ucanto/server'
 import { connect } from '@ucanto/client'
-import { AllocatedMemoryNotWrittenError, BlobSizeLimitExceededError } from '../../src/blob.js'
+import {
+  AllocatedMemoryNotWrittenError,
+  BlobSizeLimitExceededError,
+} from '../../src/blob.js'
 
 /**
  * @typedef {{
@@ -61,7 +64,12 @@ const createService = ({
         const digest = Digest.decode(capability.nb.blob.digest)
         const checksum = base64pad.baseEncode(digest.digest)
         if (capability.nb.blob.size > MaxUploadSize) {
-          return error(new BlobSizeLimitExceededError(capability.nb.blob.size, MaxUploadSize))
+          return error(
+            new BlobSizeLimitExceededError(
+              capability.nb.blob.size,
+              MaxUploadSize
+            )
+          )
         }
         if (await contentStore.has(digest)) {
           return ok({ size: 0 })
@@ -323,7 +331,7 @@ export class StorageNode {
 
 /**
  * @param {API.ClaimsClientContext} ctx
- * @param {{ space: API.SpaceDID, digest: API.MultihashDigest, location: API.URI }} params
+ * @param {{ space: Uint8Array, digest: API.MultihashDigest, location: API.URI }} params
  */
 const publishLocationCommitment = async (ctx, { digest, location }) => {
   const { invocationConfig, connection } = ctx.claimsService
diff --git a/packages/upload-api/test/handlers/blob.js b/packages/upload-api/test/handlers/blob.js
index 5ea71ce6..3a491f49 100644
--- a/packages/upload-api/test/handlers/blob.js
+++ b/packages/upload-api/test/handlers/blob.js
@@ -115,7 +115,7 @@ export const test = {
       proofs: [proof],
       // Note: we have to set an expiration, or the default expiration value
       // will be set when the invocation is executed and the UCAN issued.
-      expiration: (Math.floor(Date.now() / 1000)) + 10
+      expiration: Math.floor(Date.now() / 1000) + 10,
     })
     // Invoke `blob/add` for the first time
     const firstBlobAdd = await invocation.execute(connection)
diff --git a/packages/upload-api/test/storage/blob-registry-tests.js b/packages/upload-api/test/storage/blob-registry-tests.js
index 142bba45..13d95efa 100644
--- a/packages/upload-api/test/storage/blob-registry-tests.js
+++ b/packages/upload-api/test/storage/blob-registry-tests.js
@@ -13,7 +13,7 @@ export const test = {
     const { registry } = context
     const data = new Uint8Array([11, 22, 34, 44, 55])
     const digest = await sha256.digest(data)
-    const blob = { digest: digest.bytes, size: data.length }
+    const blob = { digest: digest, size: data.length }
     const cause = await randomCID()
     const registration = await registry.register({ space, blob, cause })
     assert.ok(registration.ok)
@@ -26,7 +26,7 @@ export const test = {
     const { registry } = context
     const data = new Uint8Array([11, 22, 34, 44, 55])
     const digest = await sha256.digest(data)
-    const blob = { digest: digest.bytes, size: data.length }
+    const blob = { digest: digest, size: data.length }
     const cause = await randomCID()
     const registration0 = await registry.register({ space, blob, cause })
     assert.ok(registration0.ok)
@@ -45,7 +45,7 @@ export const test = {
     assert.ok(find0.error)
     assert.equal(find0.error?.name, EntryNotFound.name)
 
-    const blob = { digest: digest.bytes, size: data.length }
+    const blob = { digest: digest, size: data.length }
     const cause = await randomCID()
     const registration = await registry.register({ space, blob, cause })
     assert.ok(registration.ok)
@@ -54,7 +54,9 @@ export const test = {
     assert.ok(find1.ok)
     assert.ok(find1.ok?.blob)
     assert.equal(find1.ok?.blob.size, data.length)
-    assert.ok(equals(digest.bytes, find1.ok?.blob.digest || new Uint8Array()))
+    assert.ok(
+      equals(digest.bytes, find1.ok?.blob.digest.bytes || new Uint8Array())
+    )
     assert.equal(find1.ok?.cause.toString(), cause.toString())
   },
   'should list all blobs in a space': async (assert, context) => {
@@ -65,12 +67,12 @@ export const test = {
     // Data for alice
     const data0 = new Uint8Array([11, 22, 34, 44, 55])
     const digest0 = await sha256.digest(data0)
-    const blob0 = { digest: digest0.bytes, size: data0.length }
+    const blob0 = { digest: digest0, size: data0.length }
     const cause0 = await randomCID()
     // Data for bob
     const data1 = new Uint8Array([66, 77, 88, 99, 0])
     const digest1 = await sha256.digest(data1)
-    const blob1 = { digest: digest1.bytes, size: data1.length }
+    const blob1 = { digest: digest1, size: data1.length }
     const cause1 = await randomCID()
 
     // Get alice empty entries
@@ -101,8 +103,8 @@ export const test = {
     assert.equal(entriesAlice1.ok?.results.length, 1)
     assert.ok(
       equals(
-        blob0.digest,
-        entriesAlice1.ok?.results[0].blob.digest || new Uint8Array()
+        blob0.digest.bytes,
+        entriesAlice1.ok?.results[0].blob.digest.bytes || new Uint8Array()
       )
     )
 
@@ -121,12 +123,12 @@ export const test = {
     assert.equal(entriesAlice2.ok?.results.length, 2)
     assert.ok(
       entriesAlice2.ok?.results.some((res) =>
-        equals(res.blob.digest, blob0.digest)
+        equals(res.blob.digest.bytes, blob0.digest.bytes)
       )
     )
     assert.ok(
       entriesAlice2.ok?.results.some((res) =>
-        equals(res.blob.digest, blob1.digest)
+        equals(res.blob.digest.bytes, blob1.digest.bytes)
       )
     )
   },
@@ -144,7 +146,7 @@ export const test = {
     const { registry } = context
     const data = new Uint8Array([11, 22, 34, 44, 55])
     const digest = await sha256.digest(data)
-    const blob = { digest: digest.bytes, size: data.length }
+    const blob = { digest: digest, size: data.length }
     const cause = await randomCID()
 
     const reg = await registry.register({ space, blob, cause })
diff --git a/packages/upload-api/test/storage/blob-registry.js b/packages/upload-api/test/storage/blob-registry.js
index 705890d5..a843aea2 100644
--- a/packages/upload-api/test/storage/blob-registry.js
+++ b/packages/upload-api/test/storage/blob-registry.js
@@ -13,18 +13,17 @@ export class Registry {
   /** @type {API.BlobAPI.Registry['register']} */
   async register({ space, cause, blob }) {
     const entries = this.data.get(space) ?? []
-    if (entries.some((e) => equals(e.blob.digest, blob.digest))) {
+    if (entries.some((e) => equals(e.blob.digest.bytes, blob.digest.bytes))) {
       return error(new EntryExists())
     }
-    const insertedAt = new Date().toISOString()
-    this.data.set(space, [{ blob, cause, insertedAt }, ...entries])
+    this.data.set(space, [{ blob, cause, insertedAt: new Date() }, ...entries])
     return ok({})
   }
 
   /** @type {API.BlobAPI.Registry['find']} */
   async find(space, digest) {
     const entries = this.data.get(space) ?? []
-    const entry = entries.find((e) => equals(e.blob.digest, digest.bytes))
+    const entry = entries.find((e) => equals(e.blob.digest.bytes, digest.bytes))
     if (!entry) return error(new EntryNotFound())
     return ok(entry)
   }
@@ -32,7 +31,7 @@ export class Registry {
   /** @type {API.BlobAPI.Registry['deregister']} */
   async deregister(space, digest) {
     const entries = this.data.get(space) ?? []
-    const entry = entries.find((e) => equals(e.blob.digest, digest.bytes))
+    const entry = entries.find((e) => equals(e.blob.digest.bytes, digest.bytes))
     if (!entry) return error(new EntryNotFound())
     this.data.set(
       space,
diff --git a/packages/upload-api/test/storage/usage-storage.js b/packages/upload-api/test/storage/usage-storage.js
index f364edf6..9c8e5e33 100644
--- a/packages/upload-api/test/storage/usage-storage.js
+++ b/packages/upload-api/test/storage/usage-storage.js
@@ -53,7 +53,7 @@ export class UsageStorage {
           return {
             cause: /** @type {import('../types.js').Link} */ (item.cause),
             delta: item.size,
-            receiptAt: item.insertedAt,
+            receiptAt: item.insertedAt.toISOString(),
           }
         }),
       },
diff --git a/packages/upload-client/test/helpers/utils.js b/packages/upload-client/test/helpers/utils.js
index 4194d6ce..5d3dde98 100644
--- a/packages/upload-client/test/helpers/utils.js
+++ b/packages/upload-client/test/helpers/utils.js
@@ -5,6 +5,7 @@ import { Assert } from '@web3-storage/content-claims/capability'
 import * as Server from '@ucanto/server'
 import * as HTTP from '@storacha/capabilities/http'
 import * as BlobCapabilities from '@storacha/capabilities/blob'
+import * as DID from '@ipld/dag-ucan/did'
 import { createConcludeInvocation } from '../../src/blob/add.js'
 import { randomCAR } from './random.js'
 
@@ -126,7 +127,7 @@ const setupBlobAddResponse = async function (
       nb: {
         blob,
         cause: invocation.link(),
-        space: space.did(),
+        space: DID.parse(space.did()),
       },
       expiration: Infinity,
     })
@@ -190,7 +191,7 @@ const setupBlobAddResponse = async function (
       with: space.did(),
       nb: {
         blob,
-        space: space.did(),
+        space: DID.parse(space.did()),
         _put: { 'ucan/await': ['.out.ok', blobPutTask.link()] },
       },
       proofs,
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 2c471b10..19f490ca 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -216,6 +216,9 @@ importers:
         specifier: ^5.0.3
         version: 5.1.0
     devDependencies:
+      '@ipld/dag-ucan':
+        specifier: ^3.4.0
+        version: 3.4.0
       '@storacha/eslint-config':
         specifier: workspace:^
         version: link:../eslint-config-w3up