decide

# Decisions — typed judgments from Claude Code `POST https://api.blockrun.ai/v1/decisions` takes an **input** (a message, a ticket, a diff, a tool result, an image) and a list of **questions** with a fixed answer space, and returns one typed answer per question — no prose to parse. It is compatible with OpenAI's Decisions API and served by `gpt-6-luna`. It is **not a BlockRun MCP tool**, on purpose: you are already a frontier model, and for a one-off "is this urgent?" you are the better judge. The endpoint earns its place when the user wants the *same fixed ruler over many items*, or is prototyping a judgment they will later run from a pipeline **without** a model. From Claude Code, call it with `curl` from the shell. ## Where to call it | Endpoint | Auth | Price | |---|---|---| | `https://api.blockrun.ai/v1/decisions` | `Authorization: Bearer brk_live_…` | Free for any registered key, per-key hourly limit | That is the only rail. Decisions is **not sold over x402**: the x402 per-call floor is above what a Decisions call costs, so a paid route would bill nearly every call at the floor. Do not look for it on `blockrun.ai` or `sol.blockrun.ai`, and do not offer to pay for it from the wallet. Batch the questions anyway: many questions in one call share one input and one round trip. **OpenJev is retired** (2026-10-07). The old `POST api.blockrun.ai/v1/decide` shape (`state`, `noul`/`choice`/`score` with `criteria`) is still accepted and answered by the same model, but write new calls against `/v1/decisions`. ## Getting a key without changing how the MCP pays Keys are minted at <https://user.blockrun.ai/dashboard/keys> (`brk_live_…`, shown once; registration, not a card). For experiments, **export the key in the shell** and leave the MCP server alone: ```bash export BLOCKRUN_API_KEY=brk_live_… ``` Do **not** write it to `~/.blockrun/.api-key` just to try this. The MCP server reads that file at startup and a present key moves **every** paid tool from wallet mode to account billing — the same switch `BLOCKRUN_API_KEY` in the MCP server's own config makes. That is fine if the user wants account billing (see the `blockrun-setup` skill); it is a surprise if they only wanted a free judgment. If the MCP is already on account billing, the same key works for both. ## Request ```bash curl -sS https://api.blockrun.ai/v1/decisions \ -H "authorization: Bearer $BLOCKRUN_API_KEY" \ -H "content-type: application/json" \ -D /dev/stderr \ -d '{ "model": "gpt-6-luna", "input": "Help! My payouts have been failing for 3 days.", "questions": [ { "type": "predicate", "name": "is_urgent", "instructions": "Does the message convey urgency?" }, { "type": "choice", "name": "department", "instructions": "Which team should handle this?", "choices": [ { "value": "billing", "description": "Payments, payouts, refunds" }, { "value": "technical", "description": "Bugs and outages" } ] }, { "type": "score", "name": "frustration", "instructions": "How frustrated is the customer?", "levels": [ { "label": "calm", "description": "Neutral tone" }, { "label": "frustrated", "description": "Clearly unhappy" }, { "label": "angry", "description": "Hostile or threatening to leave" } ] } ] }' ``` `-D /dev/stderr` shows the response headers (rate limit) without mixing them into the JSON on stdout. | Field | Type | Required | Notes | |---|---|---|---| | `model` | string | no | `gpt-6-luna`, the only Decisions model. | | `input` | string \| array | yes | A string, or messages whose `content` holds text and inline base64 images (no hosted URLs). If a fact matters, put it in — the model looks nothing up. | | `questions` | array | yes | Each `{ type, name, instructions }`, plus `choices` or `levels`. | | Type | You add | You get back | |---|---|---| | `predicate` | nothing | `probability` 0–1 | | `choice` | `choices: [{ value, description }]` | `choice`, `probabilities` per value, `confidence` | | `score` | `levels: [{ label, description }]`, lowest first | `score` (weighted level index from 0), `probabilities` per level, `confidence` | A question the model declines comes back as `type: "refusal"`. ## Response (measured 2026-10-07 for the request above) ```json { "model": "gpt-6-luna", "answers": [ { "type": "predicate", "name": "is_urgent", "probability": 0.95 }, { "type": "choice", "name": "department", "choice": "billing", "probabilities": [ { "value": "billing", "probability": 1.0 }, { "value": "technical", "probability": 0.0 } ], "confidence": 1.0 }, { "type": "score", "name": "frustration", "score": 0.94, "probabilities": [ { "value": 0, "label": "calm", "probability": 0.06 }, { "value": 1, "label": "frustrated", "probability": 0.94 }, { "value": 2, "label": "angry", "probability": 0.0 } ], "confidence": 0.91 } ], "usage": { "input_tokens": 399, "output_tokens": 0, "total_tokens": 399 } } ``` ## Before you build a threshold Set thresholds by running the user's **own labelled examples** through the endpoint and looking at where the errors land — not by reading a number as an accuracy. An agent that gates on `confidence > 0.8` without that check will be wrong with no error to tell it so. The model judges only the input. A question whose answer is not in it ("does this need a reply today?" over a message that says nothing about timing) still gets an answer that looks like a verdict. That one is policy — answer it in code. ## Trying it on the user's data — the shape that works 1. **Build the input** with everything the judgment needs. Fetch with `blockrun_exa` or `blockrun_search` first if a fact is missing. 2. **Ask the independent questions together** in one call. 3. **Combine with deterministic checks** the code already has. 4. **Route by margin.** Act automatically where the margin is wide *and* the checks agree; hand narrow cases to a reasoning model via `blockrun_chat`, or to a person. A quick evaluation loop: put 20–50 labelled rows in a JSON file, loop `curl` over them with `jq`, and tabulate agreement. ```bash jq -c '.[]' examples.json | while read -r row; do input=$(jq -c '.input' <<<"$row"); want=$(jq -r '.label' <<<"$row") got=$(curl -sS https://api.blockrun.ai/v1/decisions \ -H "authorization: Bearer $BLOCKRUN_API_KEY" -H "content-type: application/json" \ -d "{\"model\": \"gpt-6-luna\", \"input\": $input, \"questions\": [{\"type\": \"choice\", \"name\": \"q\", \"instructions\": \"Which team should handle this?\", \"choices\": [{\"value\": \"billing\", \"description\": \"Payments, refunds\"}, {\"value\": \"technical\", \"description\": \"Bugs, outages\"}]}]}" \ | jq -r '.answers[0].choice') echo "$want,$got" done | sort | uniq -c ``` ## Limits and errors | Status | Meaning | Charged? | |---|---|---| | 400 | Body did not match the schema; the error names the field | No | | 401 | Missing or invalid key | No | | 429 | Per-key hourly limit; wait for `retry-after` | No | | 502 / 504 | Model unreachable or timed out | No | ## Related - API reference: <https://blockrun.ai/docs/api-reference/decisions> - Account billing for the whole MCP: `blockrun-setup` skill, "API key" section.