refactor(templates): simplify agent-typescript-strands to a barebones agent

[Hweinstock]

Spec

Problem: The agent-typescript-strands template has too many parameters on the refactor branch, making it hard to read, extend, and understand.

Definition of done:

• The template describes a barebones Strands agent.
• The only rendering left is name, memory, and model provider. All other flags/templates are dropped. Memory still uses our session manager.
• We still support CodeZip and Container.

Verification (spec): create a CodeZip runtime + add a Container runtime, run dev for each and invoke locally, deploy to AWS and invoke via the CLI/AWS CLI; do both across the memory options; and verify a non-Bedrock (Gemini) provider works. This is the TypeScript analog of the merged Python PR aws#2179.

Changes

1. refactor: reduce agent-typescript-strands to a barebones agent — mirrors aws#2179 for TypeScript.

• Removed the MCP client scaffolding: deleted mcp_client/client.ts, stripped the MCP import/usage from main.ts, dropped @modelcontextprotocol/sdk from package.json.template, updated the manager.test.ts snapshot.
• The TS resolver in runtime.ts was already minimal — it never carried the gateway/payment/VPC/filesystem context that refactor(templates): simplify strands python agent to barebones agent aws/agentcore-cli#2179 stripped from the Python resolver — so no runtime.ts change was needed. The template now renders only name, memory (+ strategies), and modelProvider (+ identity providers). Memory continues to use the AgentCore MemoryManager session manager.

2. fix: pass the workload identity token to non-Bedrock providers — discovered during the Gemini deploy verification; a pre-existing bug in the non-Bedrock deploy path (not caused by the simplification).

• Deployed non-Bedrock runtimes previously failed with workloadIdentityToken not provided and no context available. The template relied on withApiKey's implicit getContext() fallback, which is unreliable inside a streamed async generator; and the pinned bedrock-agentcore ~0.3.0 read only the legacy WAT header.
• Fix: thread context.workloadAccessToken from the handler in main.ts → getOrCreateAgent → loadModel(workloadIdentityToken) → withApiKey({ providerName, workloadIdentityToken }) (all four provider branches; Bedrock accepts and ignores the param), and bump the SDK pin to ~0.4.3 (reads the current WAT header). Deployed non-Bedrock providers must be invoked with a runtime user id (--user-id), which triggers the runtime to mint & deliver the WAT.

How to test

bun run compile:linux-x64
BIN=./dist/bin/agentcore-linux-x64

# barebones scaffold — CodeZip + Bedrock + longAndShortTerm (default)
$BIN project create --name simpleTsStrands --template agent-typescript-strands
cd simpleTsStrands
# add a Container runtime (memory none) and a Gemini runtime (memory none)
$BIN project add runtime --name tsContainer --template agent-typescript-strands --build Container --memory none
$BIN project add runtime --name tsGemini --template agent-typescript-strands --model-provider gemini --api-key file://<gemini.key> --memory none

# local dev (headless) then invoke each
$BIN project dev --mode headless --no-traces &
for P in <ports>; do curl -s -X POST localhost:$P/invocations \
  -H 'accept: text/event-stream' -H 'content-type: application/json' \
  -H "x-amzn-bedrock-agentcore-runtime-session-id: local-session-000000000000000000000001" \
  -d '{"prompt":"Say hello in exactly 3 words"}'; done

# deploy + invoke on AWS (Gemini needs --user-id to receive a workload token)
$BIN project deploy
$BIN project invoke runtime --name agent_typescript_strands --accept text/event-stream --payload '{"prompt":"hi"}'
$BIN project invoke runtime --name tsContainer          --accept text/event-stream --payload '{"prompt":"hi"}'
$BIN project invoke runtime --name tsGemini --user-id demo-user --accept text/event-stream --payload '{"prompt":"hi"}'

Verification evidence (dev account, us-east-1)

Barebones scaffold — generated source is just main.ts, memory/memory.ts, model/load.ts, package.json, tsconfig.json (+ README/.gitignore); no mcp_client/, no @modelcontextprotocol/sdk.

Memory options (TS): none and longAndShortTerm scaffold, deploy, and invoke. shortTerm is rejected with a clear, pre-existing validation error (the TS SDK's createAgentCoreMemoryStores requires ≥1 long-term namespace):

$ agentcore project add runtime --name tsShort --template agent-typescript-strands --memory shortTerm
Error: the agent-typescript-strands template does not support short-term-only memory; add long-term strategies or use --memory none

Local dev (final template, all three invokable):

port 8087 (Gemini/none):            "Hello there" "! Hi."
port 8088 (Bedrock CodeZip/L&S):    "Hello to" " you!"
port 8089 (Bedrock Container/none): "Hello to" " you!"

AWS deploy: stack AgentCore-simpleTsStrands-default → CREATE_COMPLETE (3 runtimes + AgentCore Memory + Gemini credential provider).

Deployed invoke (all HTTP 200):

codezip/Bedrock  (agentcore invoke):  "Hi there" "!"      status=200
codezip/Bedrock  (raw aws bedrock-agentcore invoke-agent-runtime):  "Hi there!"  statusCode 200
container/Bedrock:                     "Hi" " there!"     status=200
codezip/Gemini   (--user-id):          "Hi" " there!"     status=200

Notes

• Kept the change un-generalized per the spec: the TS template mirrors the Python one rather than unifying them.
• The pre-commit hook mis-fires on assets-only commits (oxlint --fix → "No files found to lint" because template/snapshot paths are oxlint-ignored); committed with --no-verify after running typecheck / lint:check / format:check / full bun test (2824 pass) on the whole tree. CI re-runs them.