the-metis-fca-handbook-ai-harness-mcp

Evaluate which FCA Handbook entries apply to a situation as input by the user, using the Metis FCA Handbook AI Harness.

Calls a live compliance reasoning run, billed to the configured account. Use for questions involving the FCA Handbook, including authorisation, permissions, or obligations for a specific firm/product/service.

This call takes 60-120 seconds in 'quick' mode and 90-120 seconds in 'full' mode, and the longest stretch, the main reasoning step (node 6), shows nothing new on the user's screen, so it can look as if the call has crashed. Before you call the tool, always tell the user in plain words that the Harness is about to do substantial reasoning work, that this takes a minute or two, and that it has not crashed if the screen is quiet. Do not go silent. The Harness attempts to stream progress messages as each reasoning node completes - if you receive them, relay each one to the user as it arrives — they contain genuine detail, not filler.

Billing rule: every call is a separate charge. After a result arrives, never start another call, whether 'quick' or 'full', in the same turn or without the user's explicit yes to that specific further run, even when the refinement suggestions make another pass look clearly worthwhile.

First call: use analysis_mode='quick'. Before calling, check whether you already have (from this conversation, documents you were given, or other tools) grounded answers to these six things — the specific compliance question, the product/service, who is providing it (platform/adviser/ bank/etc.), its key features, the target market (retail/institutional/ professional/customer segment), and what data it handles. If you are missing more than one or two, ask the user for them first rather than calling with thin input. Every call is billed at a flat rate regardless of input quality, so a vague call incurs unnecessary cost.

The result includes refinement_suggestions — gaps the Harness could not resolve from user_input alone, typically subtler than the six basics above (e.g. a regulatory edge case, not a missing fact you could have just asked for). For each suggestion worth pursuing, get the grounded information — retrieve it from this conversation, documents you were given, or other tools if you already have it; otherwise ask the user directly. Do not speculate or infer plausible-sounding detail you do not actually have — that reintroduces the hallucination risk this Harness exists to avoid, one level up.

Refining (second call onward): use analysis_mode='full'. Either way, before calling again, stop and ask the user whether they want a further 'full' pass with the refined input, saying that it is a further charge, and wait for their answer — never call again unilaterally, and do not just list the gaps and stop. Repeat this pattern for further rounds if the new result still leaves suggestions worth resolving.

The result's citations field contains verbatim quotes from the FCA Handbook — this is a core part of what the Harness offers, not generative invention, and distinct from the summary/obligations text. They can best be viewed as an Appendix. Citations can be long, so ask the user whether they want the relevant verbatim citations included, rather than omitting them by default as mere detail.

Args: user_input: Everything together as one piece of text (up to 5000 characters) — the specific compliance question, the product/service, who is providing it, its key features, the target market, and what data it handles. On later rounds, refine all six using existing chat context and whatever additional detail later rounds have gathered. See "First call" and "Refining" above. analysis_mode: 'quick' for the first call (default, ~60-120 seconds); 'full' (~90-120 seconds) for refined calls after the first — detailed conditional reasoning: conditions, interactions between rules, and second-order implications. See "Refining" above for when to switch and why to confirm with the user first.