Clients and models

Ansvar works with any MCP client that supports Streamable HTTP and OAuth. For search and provision lookups, client and model choice barely matters. For workflows — threat models, gap analyses, DPIAs — it matters a lot. This page states what workflows demand of a client, which client capabilities meet that demand, which models we have tested, and the per-client limits worth designing around.

Workflow availability by plan: Premium runs threat-modeling workflows on a system you describe (metered monthly); Team and Company run the full catalog, including workflows over your own documents. See pricing.

What a workflow asks of your client

Measured against the live gateway on 2026-07-05 (STRIDE threat model, standard walk):

  • 15 server-enforced steps. A typical walk takes 2–4 hours of session time — long enough that the gateway supports resume_workflow for OAuth tokens that expire mid-run. Save the workflow_id the gateway returns.
  • MCP prompts, not just tools. Steps direct the client to invoke prompts such as /threat-modeler-scope-check. A client without prompt support can still proceed, but the operator pastes prompt text by hand at each step.
  • Parallel sub-analyses. For the STRIDE enumeration phase alone, the gateway's recommend_subagents planner recommends 6 parallel subagent prompt-runs. Clients that cannot spawn subagents get an inline fallback: the same work, sequential, in one context window.
  • Large tool results. One search call queried roughly 27 corpus servers and returned about 10 KB of cited rows. A full workflow walk accumulates tens to hundreds of kilobytes of fetched regulatory text in the client's context.

Client capabilities that matter

CapabilityNeeded forWithout it
MCP tools over Streamable HTTP + OAuthEverythingCannot connect — see Setup and Clients without OAuth
MCP promptsWorkflow step executionPaste prompt text manually per step
Subagents / parallel task spawningWorkflow fan-out phasesInline fallback: sequential, single context — works, degrades on large systems
Large context window (model and client limits both apply)Multi-pass enrichment, long workflowsContext truncation mid-workflow; run one pass or stage at a time

Search and lookups work on any client with Streamable HTTP + OAuth support. Setup walkthroughs exist for Claude (web + Desktop), Claude Code, VS Code / GitHub Copilot, Cursor, ChatGPT, Copilot Studio, Gemini, and Azure AI Foundry.

Workflows are strongest on clients with subagent and prompt support (Claude Desktop, Claude Code). On tools-only agent clients (GitHub Copilot agent mode and similar), workflows run through the inline fallback: expect longer sessions, keep the system description tight, and run enrichment passes one at a time. We have not yet load-tested a full workflow walk on Copilot agent mode; that guidance follows from the fallback path's design, not from a Copilot-specific run.

Per-client limits to design around

Observed in live triage during 2026-07 — client properties, not model properties, and independent of your plan:

  • ChatGPT — no MCP prompt support (use describe_capabilities with section="tour" instead of the ansvar-tour prompt); a hard per-call timeout near 60 seconds with automatic duplicate retry (normal searches finish in a few seconds, so this bites only on very large scopes); instruction fields weight their opening lines heavily — put the scope rule first. Long chats have been observed dropping tools from context; a fresh chat restores them.
  • Copilot Studio — the orchestrator follows the agent's Instructions field, not hints inside tool responses, so retry and broadening rules must live in the instructions. See Connect Copilot Studio for the connection-lifecycle warnings.
  • Claude (web, Desktop, Code) — full MCP surface: tools, prompts, and (in Claude Code) subagents. This is the reference client for workflow walks.

What to look for in a model

Ansvar exposes up to a few dozen tools depending on plan, and real regulatory research is an agentic loop: scope, search, read, re-scope, cite. The model qualities that matter, in order:

  1. Reliable tool calling — correct arguments across many tools, many turns. This is the floor; a model that fumbles tool schemas fails regardless of its reasoning quality.
  2. Recovery behaviour — when a scoped query returns zero or noisy rows, does the model re-scope (switch query language, switch scope type, split the query) or accept the empty result and move on? Over a 15-step workflow this difference compounds.
  3. Instruction following — the agent instructions only work if the model obeys them under pressure, including the refusal rule when results are empty.
  4. Context capacity — workflows accumulate large fetched-text volumes; small context windows truncate mid-run.

Tested model configurations

Same task, same prompt, same account, run 2026-07-05: a five-pass regulatory enrichment scan (primary regime, horizontal regimes, sector routing, case law, authority guidance) for a German telehealth scenario, with a 15-call budget. Only Claude rows are filled so far because the test harness runs the protocol as Claude subagents — the GPT and Gemini runs are queued, and until they execute those rows stay honestly empty rather than guessed.

ModelResultNotes
Claude Opus 4.85/5 passes, 7 gateway callsReasoned about fan-out semantics — re-scoped a query to reach the case-law corpus; precise citations; excluded off-topic rows
Claude Sonnet 55/5 passes, 9 gateway callsRecovered from an English-query miss on a German-language corpus by retrying in German; deepest national sector-law detail
Claude Haiku 4.54/5 passes, 12 gateway callsReported the unresolved pass honestly, but stopped after one empty result instead of re-scoping; one imprecise citation
GPT (OpenAI)Not yet tested on this protocolSee the reasoning-effort note below
GeminiNot yet tested

What separates the tiers is recovery. Real regulatory research hits scoped queries that return zero or noisy rows. Frontier models re-scope — switch query language, switch scope type — and recover; smaller models tend to accept the empty result and move on.

Practical guidance

  • Use a frontier model with strong tool use for workflows. Smaller models handle simple searches fine.
  • Query national corpora in their own language — and put that rule in the agent instructions, not in the user's hands.
  • Expect long workflow sessions. Save the workflow_id and use resume_workflow after a token expiry.

Method

Model rows: one run per model (n=1), identical prompts, executed as agent-harness subagents against the production gateway on a company-tier account, 2026-07-05. This is a directional capability check, not a benchmark. Rows for Copilot, GPT, and Gemini stay unfilled until the same protocol runs on those surfaces. Workflow-demand numbers come from a live threat-model walk (15 steps, cancelled after measurement) and the gateway's recommend_subagents planner, same date. Per-client limits come from live customer triage in 2026-07; the OpenAI reasoning-effort finding comes from an internal qualification run on 2026-07-10.