Design agreed in discussion, nothing built yet. Records the agent's role, its scopes and MCP servers, its A2A surface, and the framework choice with its reason — so the next session starts from the decisions rather than re-deriving them. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
7.2 KiB
classic-models-agent-platform
Shared ground for the classic-models agent estate: templates, conventions, and
the identity plumbing every agent repeats. Plays the role kong-k8s-platform
plays for the gateways.
Nothing runs from this repo. It holds the ${VAR}-parameterised manifests a
domain's Flux Kustomization builds, plus the reference documentation below.
The estate this plugs into
The agents replace LibreChat as the MCP client and orchestrator. Everything
below them already exists and does not change: Kong gateways per domain, MCP
servers served by Kong's ai-mcp-proxy, Keycloak, and the domain APIs.
| Agent | Repo | Framework | Mode |
|---|---|---|---|
| Assistant | classic-models-agent-assistant |
LangGraph | conversational |
| Ventes | classic-models-agent-ventes |
CrewAI | conversational |
| Catalogue | classic-models-agent-catalogue |
PydanticAI + FastA2A | conversational |
| Support | classic-models-agent-support |
Google ADK | conversational |
| Approvisionnement | classic-models-agent-flows |
n8n | autonomous |
| Recouvrement | classic-models-agent-flows |
n8n | autonomous |
Five runtimes is deliberate. The point is proving A2A interoperability between stacks that do not know each other; a single framework would prove nothing.
Topology
A2A between agents, MCP between an agent and data.
Assistant ──→ every agent (orchestration; holds no scopes itself)
Ventes ──→ Approvisionnement, Recouvrement
Support ──→ Ventes
Catalogue ──→ Approvisionnement
An A2A call returns an answer, not data. Ventes asks Approvisionnement "can
I promise delivery on 15 March?" and receives yes/no — it never gains read
access to the catalog domain. Agent Cards therefore expose narrow,
decision-shaped skills (check_availability, check_creditworthiness), never a
generic query. An agent that exposes "ask me anything about my domain" has
become a data proxy and defeats the scoping.
The Assistant holds no scopes at all. It is the component that sees raw user text, so it is the prompt-injection target, and it must be unable to exfiltrate anything.
Identity
Each agent is its own Keycloak client. That is what makes the actor
identifiable: the exchanged token carries azp = the agent's client id
alongside sub = the end user.
{ "sub": "alice", "azp": "classic-models-agent-ventes",
"aud": ["mcp-catalog"], "scope": "openid profile email mcp-catalog-audience" }
Two measured facts that constrain the implementation:
actor_token is silently ignored. Keycloak 26.6's Standard Token Exchange
accepts the parameter, returns a valid token, and emits no act claim. No
error. Do not build delegation on RFC 8693 act — use azp.
The audience is requested via a scope, not the audience parameter. Passing
audience=mcp-catalog returns Requested audience not available. Pass
scope=openid mcp-catalog-audience.
The exchange
Do what LibreChat already does — a POST per target audience, roughly twenty lines. Do not build a sidecar or move the exchange into Kong; both were considered and rejected as over-engineering, the second also because it would leave the agent holding one broad token instead of several narrow ones.
POST https://keycloak.sttlab.local/realms/classic-models/protocol/openid-connect/token
grant_type=urn:ietf:params:oauth:grant-type:token-exchange
client_id=<the agent's client id>
client_secret=<from the agent's Secret>
subject_token=<the end user's access token>
subject_token_type=urn:ietf:params:oauth:token-type:access_token
scope=openid mcp-<domain>-audience
Neither LangGraph nor CrewAI injects a per-call MCP token natively
(langchain-mcp-adapters issues #172/#194/#235; CrewAI's MCPServerAdapter fixes
headers at construction). This is a non-issue: build the MCP client once per
conversation turn with freshly exchanged tokens. A turn lasts seconds, an
access token five minutes.
Endpoints
MCP servers, one per domain, served by Kong:
| Domain | URL | Audience scope |
|---|---|---|
| catalog | https://catalog-dev.sttlab.local/catalog-mcp |
mcp-catalog-audience |
| customers | https://customers-dev.sttlab.local/customers-mcp |
mcp-customers-audience |
| payments | https://payments-dev.sttlab.local/payments-mcp |
mcp-payments-audience |
| sales | https://sales-dev.sttlab.local/sales-mcp |
mcp-sales-audience |
| workforce | https://workforce-dev.sttlab.local/workforce-mcp |
mcp-workforce-audience |
LLM inference goes through the Kong AI gateway, never direct to a provider:
https://llm-dev.sttlab.local/llm/v1/chat/completions
It applies rate limiting, prompt guards and semantic guards, and routes to OpenRouter. Sending inference anywhere else bypasses all of them.
These hostnames are lab-only with a self-signed certificate. /etc/hosts:
192.168.139.103 catalog-dev.sttlab.local
192.168.139.105 llm-dev.sttlab.local
192.168.139.106 customers-dev.sttlab.local
192.168.139.107 payments-dev.sttlab.local
192.168.139.108 sales-dev.sttlab.local
192.168.139.109 workforce-dev.sttlab.local
192.168.139.101 keycloak.sttlab.local
The CA is sttlab-local-ca (cert-manager ClusterIssuer). Trust that one CA
rather than disabling verification.
Adding an agent
An agent is a declaration first. Put it here, let the generator produce the rest — the Keycloak client is generated from this, never hand-written in the agent's own repo, so the realm stays the single source of truth.
name: ventes
client_id: classic-models-agent-ventes
framework: crewai
surfaces: [conversational]
mcp_servers: [catalog, sales]
scopes: [catalog:read, sales:read, sales:write]
a2a_calls: [approvisionnement, recouvrement]
limits:
max_tool_calls_per_run: 20
max_records_read_per_run: 500
scopes becomes the client's optionalClientScopes; mcp_servers becomes the
audience scopes it may request; a2a_calls becomes the A2A authorisations.
The realm actually deployed is infra-keycloak/k8s/keycloak/configmap-realm.yaml
— note that kong-v2/classic-models-realm.yaml is an older partial copy and is
not authoritative.
Known blockers
Konnect is not persisting configuration. The operator loops on the same objects without converging and the dataplanes stay behind the control plane, so no new Kong config reaches the gateways — including any new agent audience. Resolve this before expecting an end-to-end run.
No employeeNumber in tokens. Sales territory scoping (a rep sees their
territory, a manager sees all) resolves through
employee → officeCode → offices.territory, but the token carries no employee
identity, so the API cannot filter server-side. The realm's users
(admin-user, pm-user, …) are role placeholders, not real employees.
The kong-token-exchange-broker secret does not match the realm — its
client_credentials returns unauthorized_client.
Conventions
- Deliverables in English: code, comments, READMEs, Agent Cards. Conversation with the maintainer is in French.
- GitOps throughout. Never
kubectl applyan object carryingkustomize.toolkit.fluxcd.io/name— Flux reverts it within its interval, and tests run against config that no longer exists. - Secrets never committed. Follow the
secret.example.yamlpattern used by theinfra-*repos.