Centralize account-ID resolution; upgrade agents/MCP SDK/zod/ai; migrate to registerTool

[mattzcarey]

Summary

A sequence of related changes on this branch (each its own commit):

1. Centralize Cloudflare account-ID resolution and remove the account-management tools.
2. Remove the now-dormant UserDetails Durable Object (+ DO deletion migration).
3. Upgrade core deps: agents 0.2.19 → 0.13.3, @modelcontextprotocol/sdk 1.20.2 → 1.29.0, zod 3 → 4, ai 4 → 6.
4. Migrate tool registration from the deprecated .tool() API to .registerTool().
5. Migrate the test suite to Vitest 4 + @cloudflare/vitest-pool-workers 0.16.
6. Get the evals running through a BYOK AI Gateway.
7. Make the generated worker types current (drop --include-env=false).

Supersedes #316 (per-tool account_id) — this is a superset, so #316 can be closed.

⚠️ This PR requires a manual, ordered deploy — see Deployment below.

1. Account-ID resolution

Removes accounts_list and set_active_account (and the per-app getActiveAccountId/setActiveAccountId). Account scoping is now resolved by a single AccountManager (packages/mcp-common/src/account-manager.ts) via a new server.accountTool() wrapper, in priority order:

1. Auth-pinned — an account-scoped API token's account, or an OAuth token with exactly one account (no account_id parameter is exposed in this case).
2. cf-account-id request header — set by the user in their MCP client config (multi-account tokens).
3. account_id tool argument — auto-appended to account-scoped tools only for multi-account tokens; when omitted (and no header) the tool returns an error listing the available accounts. Multi-account tokens also get their account list injected into the server initialize instructions for discovery.

All tool error responses now set isError: true.

2. Remove the UserDetails Durable Object

UserDetails existed only to persist activeAccountId across sessions for the old set_active_account flow (added in #85). Account resolution is now derived per-request, so nothing reads or writes it. This PR:

• Deletes user_details.do.ts and removes the USER_DETAILS binding, export, and Env type from all 13 account-scoped apps (dev + staging + production).
• Adds a deleted_classes DO migration (tag v2) to the two owning workers — workers-observability and workers-builds — so the namespace is torn down.
• The other 11 apps were cross-binders (they referenced observability's UserDetails via script_name in staging/prod); their bindings are removed.
• Strips dead commented-out tool blocks in r2_bucket.tools.ts / hyperdrive.tools.ts that referenced the removed getActiveAccountId.

3. Dependency upgrade

• zod 4: z.record(key, value) explicit key; z.string().ip() → z.ipv4()/z.ipv6(); dropped removed objectOutputType (→ z.infer<z.ZodObject<Shape>>).
• agents 0.13: McpAgent env generic constrained to Cloudflare.Env; createApiHandler/handleApiTokenMode infer the env generic (no any); MCPClientManager takes a storage option (eval clients).
• MCP SDK 1.29: tool annotations must be flat ({ title, readOnlyHint, ... }) — fixes a latent bug where nested annotations: {...} hints were silently ignored.
• ai 6: eval tooling updated (LanguageModel, inputSchema, stopWhen/stepCountIs, tool-call input).

4. registerTool migration

CloudflareMCPServer wraps both tool() and registerTool() for metrics via one shared helper. accountTool() and all remaining .tool() call sites use .registerTool(name, { description, inputSchema, annotations }, cb). No @ts-ignore / any introduced.

5. Vitest 4 + pool-workers 0.16

• defineConfig + the cloudflareTest({...}) Vite plugin (replaces defineWorkersConfig / poolOptions.workers); root vitest.config.ts with test.projects (replaces vitest.workspace.ts).
• Packages set "type": "module" (pool-workers 0.16 main entry is ESM-only).
• fetchMock was removed from cloudflare:test → migrated those specs to MSW (http / HttpResponse / setupServer).

6. Evals

• Eval models route through the user's AI Gateway using its stored (BYOK) keys via ai-gateway-provider's createUnified() — no per-provider key in the repo.
• Subjects: openai/gpt-5.4-mini, openai/gpt-4.1, workers-ai/@cf/moonshotai/kimi-k2.6; judge: openai/gpt-5.4-nano.
• Eval clients connect over /mcp (token-mode servers don't serve /sse).
• KV evals pass end-to-end; the hyperdrive evals fail only because the dev token lacks Hyperdrive read permission (not a code issue).

7. Worker types currency

• Removed --include-env=false from every app's types script (and run-wrangler-types). Under wrangler 4.96 that flag also strips the global interface Env the app/test code relies on (getEnv<Env>, McpAgent<Env>, vitest TestEnv extends Env).
• Regenerated worker-configuration.d.ts across the repo to the wrangler 4.96 / workerd 1.20260529 runtime types (this also brought @cf/google/embeddinggemma-300m into AiModels, so the docs-vectorize embeddings tool typechecks without @ts-expect-error).
• Two small source adjustments the new runtime types required: drop public from the ctx: DurableObjectState constructor params in docs-* / sandbox-container (new DurableObjectState<unknown> default conflicted with the McpAgent/DurableObject base's <{}>); assign auth props through a typed mutable view since ExecutionContext.props is now readonly.

Breaking / behavior changes

• accounts_list and set_active_account are removed.
• Tool annotation hints (readOnlyHint / destructiveHint) now actually apply (were silently dropped before).
• Multi-account OAuth users must pass account_id or set a cf-account-id header.

Deployment

This must be deployed manually, in order, because the UserDetails deletion interacts with cross-script bindings:

1. Deploy the 11 cross-binder apps (ai-gateway, auditlogs, autorag, browser-rendering, cloudflare-one-casb, dex-analysis, dns-analytics, graphql, logpush, radar, workers-bindings) and workers-builds first — their UserDetails bindings are now removed.
2. Deploy workers-observability last — it owns the shared UserDetails DO that the cross-binders referenced via script_name, and its deleted_classes migration can only run once nothing else binds the class.

Deploying workers-observability before the cross-binders are updated will fail the migration (or break a lagging cross-binder's deploy). Existing UserDetails instances and their stored activeAccountId data are dropped by the migration; nothing reads that data anymore.

Verification

• check:types, check:lint, check:format, check:deps (syncpack) all green across the workspace; tests pass.
• eval:ci runs end-to-end against a local server through the AI Gateway (see §6).
• react / ai peer-dep warnings from agents 0.13 are harmless (this repo doesn't use react).

Changesets

• centralize-account-id-resolution (minor, 13 account servers).
• upgrade-agents-mcp-sdk-zod-ai (patch, all 18 apps).