fix: update discovery profile specification links

Outdated links pointing to 'https://ucp.dev/specs/shopping' were returning 404 errors. This change updates all discovery profiles and documentation in the samples repository to use the current 'https://ucp.dev/specification' structure.

- rest/python/server: Updated 'discovery_profile.json' and 'README.md'.
- rest/python/client: Regenerated 'happy_path_dialog.md' by running the updated server and client.
- rest/nodejs: Updated discovery service logic in 'discovery.ts'.
- a2a/business_agent: Updated 'ucp.json' and 'agent_card.json' data files.
- a2a/chat-client: Updated 'agent_profile.json'.

These updates ensure that discovery responses from sample implementations point to valid, working specification pages.

Author: 0x8000-0000

a2a/business_agent/src/business_agent/data/agent_card.json

@@ -10,20 +10,20 @@
             {
               "name": "dev.ucp.shopping.checkout",
               "version": "2026-01-11",
-              "spec": "https://ucp.dev/specs/shopping/checkout",
+              "spec": "https://ucp.dev/specification/checkout",
               "schema": "https://ucp.dev/schemas/shopping/checkout.json"
             },
             {
               "name": "dev.ucp.shopping.fulfillment",
               "version": "2026-01-11",
-              "spec": "https://ucp.dev/specs/shopping/fulfillment",
+              "spec": "https://ucp.dev/specification/fulfillment",
               "schema": "https://ucp.dev/schemas/shopping/fulfillment.json",
               "extends": "dev.ucp.shopping.checkout"
             },
             {
               "name": "dev.ucp.shopping.discount",
               "version": "2026-01-11",
-              "spec": "https://ucp.dev/specs/shopping/discount",
+              "spec": "https://ucp.dev/specification/discount",
               "schema": "https://ucp.dev/schemas/shopping/discount.json",
               "extends": "dev.ucp.shopping.checkout"
             }

a2a/business_agent/src/business_agent/data/ucp.json

@@ -4,7 +4,7 @@
     "services": {
       "dev.ucp.shopping": {
         "version": "2026-01-11",
-        "spec": "https://ucp.dev/specs/shopping",
+        "spec": "https://ucp.dev/specification/shopping",
         "a2a": {
           "endpoint": "http://localhost:10999/.well-known/agent-card.json"
         }
@@ -14,13 +14,13 @@
       {
         "name": "dev.ucp.shopping.checkout",
         "version": "2026-01-11",
-        "spec": "https://ucp.dev/specs/shopping/checkout",
+        "spec": "https://ucp.dev/specification/checkout",
         "schema": "https://ucp.dev/schemas/shopping/checkout.json"
       },
       {
         "name": "dev.ucp.shopping.fulfillment",
         "version": "2026-01-11",
-        "spec": "https://ucp.dev/specs/shopping/fulfillment",
+        "spec": "https://ucp.dev/specification/fulfillment",
         "schema": "https://ucp.dev/schemas/shopping/fulfillment.json",
         "extends": "dev.ucp.shopping.checkout"
       }

a2a/chat-client/profile/agent_profile.json

@@ -5,20 +5,20 @@
       {
         "name": "dev.ucp.shopping.checkout",
         "version": "2026-01-11",
-        "spec": "https://ucp.dev/specs/shopping/checkout",
+        "spec": "https://ucp.dev/specification/checkout",
         "schema": "https://ucp.dev/schemas/shopping/checkout.json"
       },
       {
         "name": "dev.ucp.shopping.fulfillment",
         "version": "2026-01-11",
-        "spec": "https://ucp.dev/specs/shopping/fulfillment",
+        "spec": "https://ucp.dev/specification/fulfillment",
         "schema": "https://ucp.dev/schemas/shopping/fulfillment.json",
         "extends": "dev.ucp.shopping.checkout"
       },
       {
         "name": "dev.ucp.shopping.discount",
         "version": "2026-01-11",
-        "spec": "https://ucp.dev/specs/shopping/discount",
+        "spec": "https://ucp.dev/specification/discount",
         "schema": "https://ucp.dev/schemas/shopping/discount.json",
         "extends": "dev.ucp.shopping.checkout"
       },

rest/nodejs/src/api/discovery.ts

@@ -30,7 +30,7 @@ export class DiscoveryService {
         services: {
           'dev.ucp.shopping': {
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping',
+            spec: 'https://ucp.dev/specification/shopping',
             rest: {
               schema: 'https://ucp.dev/services/shopping/openapi.json',
               endpoint: 'http://localhost:3000',
@@ -41,54 +41,54 @@ export class DiscoveryService {
           {
             name: 'dev.ucp.shopping.checkout',
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping/checkout',
+            spec: 'https://ucp.dev/specification/checkout',
             schema: 'https://ucp.dev/schemas/shopping/checkout.json',
           },
           {
             name: 'dev.ucp.shopping.order',
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping/order',
+            spec: 'https://ucp.dev/specification/order',
             schema: 'https://ucp.dev/schemas/shopping/order.json',
           },
           {
             name: 'dev.ucp.shopping.refund',
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping/refund',
+            spec: 'https://ucp.dev/specification/refund',
             schema: 'https://ucp.dev/schemas/shopping/refund.json',
             extends: 'dev.ucp.shopping.order',
           },
           {
             name: 'dev.ucp.shopping.return',
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping/return',
+            spec: 'https://ucp.dev/specification/return',
             schema: 'https://ucp.dev/schemas/shopping/return.json',
             extends: 'dev.ucp.shopping.order',
           },
           {
             name: 'dev.ucp.shopping.dispute',
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping/dispute',
+            spec: 'https://ucp.dev/specification/dispute',
             schema: 'https://ucp.dev/schemas/shopping/dispute.json',
             extends: 'dev.ucp.shopping.order',
           },
           {
             name: 'dev.ucp.shopping.discount',
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping/discount',
+            spec: 'https://ucp.dev/specification/discount',
             schema: 'https://ucp.dev/schemas/shopping/discount.json',
             extends: 'dev.ucp.shopping.checkout',
           },
           {
             name: 'dev.ucp.shopping.fulfillment',
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping/fulfillment',
+            spec: 'https://ucp.dev/specification/fulfillment',
             schema: 'https://ucp.dev/schemas/shopping/fulfillment.json',
             extends: 'dev.ucp.shopping.checkout',
           },
           {
             name: 'dev.ucp.shopping.buyer_consent',
             version: this.ucpVersion,
-            spec: 'https://ucp.dev/specs/shopping/buyer_consent',
+            spec: 'https://ucp.dev/specification/buyer_consent',
             schema: 'https://ucp.dev/schemas/shopping/buyer_consent.json',
             extends: 'dev.ucp.shopping.checkout',
           },