read.markets/app/services/output_review.py
Giorgio Gilestro 385c5fdc60 review: strip markdown code-fences from JSON verdicts
Haiku 4.5 occasionally wraps its JSON response in a markdown code
fence even with response_format={"type":"json_object"} enforced:

    ```json
    {"clean": true, "reason": "polished read"}
    ```

Live testing the new reviewer caught this — every verdict was being
dropped as "reviewer returned non-JSON". Strip a single leading
trailing fence before json.loads. Defensive for any model that does
the same (Claude variants commonly fence JSON even when told not to).

Adds a unit test covering fenced output.
2026-05-29 13:27:37 +02:00

143 lines
6.2 KiB
Python

"""Second-pass reviewer agent for AI-generated reads.
The per-group and aggregate indicator summaries are generated in JSON
mode and the publishable text comes out of a single "read" field, but a
misbehaving model can still slip chain-of-thought INSIDE the field
("Let's see…", "X? Actually Y?", multi-question parentheticals). This
module makes a small second LLM call that judges the candidate read as
clean / unclean. Cost is ~$0.0001 per check; latency ~1-2 s in the
hourly job. No user-facing latency.
The reviewer is deliberately a tiny, JSON-shaped classifier — same
JSON-mode mechanism as the generator, so the verdict can't be lost in
prose. If parsing fails or the call errors, the row is rejected
(fail-safe: the previously cached good summary stays visible).
"""
from __future__ import annotations
import json
from dataclasses import dataclass
import httpx
from app.config import get_settings
from app.logging import get_logger
from app.services.openrouter import call_llm
log = get_logger("output_review")
# The reviewer runs through OpenRouter against a small, non-thinking
# model. DeepSeek-V4-flash (our generator default) emits internal
# chain-of-thought before its JSON output even when the prompt forbids
# it, which truncates the JSON at any reasonable max_tokens cap and
# breaks the parser. Anthropic's Haiku family answers structured-output
# tasks tersely and deterministically — no chain-of-thought tax. Cost
# is ~$0.0001-$0.0003 per review depending on candidate length.
DEFAULT_REVIEWER_MODEL = "anthropic/claude-haiku-4.5"
_SYSTEM_PROMPT = """\
You are a strict editor for a financial-markets dashboard. The author
was asked to produce a short interpretive read for human readers.
You receive their proposed read and decide if it is publishable as-is.
Mark CLEAN only if the text reads like a finished interpretation a
reader could see on a public dashboard without confusion.
Mark UNCLEAN if the text contains ANY of:
- Chain-of-thought / scratchpad markers used as thinking — phrases like
"Let me", "Let's see", "we need to", "actually" (correcting itself),
"wait", "hmm", "or rather", "I should".
- Self-questioning parentheticals: "Q1 2026? Actually Q4 2025?",
"is it X or Y?", any place where the author appears to be working
out the answer in front of the reader.
- Multiple rhetorical questions or any question that interrupts the
declarative voice. A clean interpretive read is assertive.
- Meta-commentary about the task, output format, word limits, or
instructions — e.g. "as required by the constraints", "the prompt
asks", "let me address each".
- Partial / truncated content. Starts mid-word, mid-number, mid-clause.
- Visible internal numbers without clear meaning ("change 1y +5.9%?"),
raw column names ("as_of 2026-01-01"), or any debug-like fragments.
- Anything other than the finished, publishable interpretation.
Return ONLY a JSON object with this exact shape:
{"clean": true | false, "reason": "<≤20 words, plain text>"}
No preamble, no markdown fences, no other fields.
"""
@dataclass(frozen=True)
class Verdict:
clean: bool
reason: str
cost_usd: float | None # cost of the review call itself, for the ledger
async def review_read(client: httpx.AsyncClient, candidate: str) -> Verdict:
"""Ask the LLM whether `candidate` is a publishable read.
Returns Verdict(clean, reason, cost). Any error — provider failure,
JSON parse failure, missing field, wrong type — yields a CONSERVATIVE
verdict (clean=False) so the caller drops the candidate. The
previously cached good summary stays visible on the dashboard."""
if not candidate or not candidate.strip():
return Verdict(clean=False, reason="empty candidate", cost_usd=0.0)
messages = [
{"role": "system", "content": _SYSTEM_PROMPT},
# Sent as a fenced user turn so the model can't confuse the
# candidate with instructions, even if the candidate happens to
# contain prompt-like prose.
{"role": "user", "content": f"Candidate read:\n```\n{candidate}\n```"},
]
settings = get_settings()
reviewer_model = getattr(settings, "REVIEWER_MODEL", None) or DEFAULT_REVIEWER_MODEL
try:
result = await call_llm(
client, messages,
# Pin to OpenRouter so a non-DeepSeek model like Haiku is
# actually reachable; the default provider chain would try
# DeepSeek native first and 404 on the Anthropic model name.
provider="openrouter",
model=reviewer_model,
# 300 tokens is well above the ~30-token JSON verdict.
# Haiku doesn't pad with hidden reasoning the way DeepSeek
# does, so we don't need the 800-token headroom required to
# absorb the generator's chain-of-thought.
max_tokens=300,
response_format={"type": "json_object"},
)
except Exception as e:
log.warning("review.call_failed", error=str(e)[:200])
return Verdict(clean=False, reason=f"reviewer error: {str(e)[:80]}",
cost_usd=None)
# Haiku (and several other models) occasionally wrap their JSON
# output in a markdown code fence even with response_format set —
# ```json\n{...}\n``` — so strip a single leading/trailing fence
# before parsing. We do this defensively for any model; it's a
# no-op for callers that already emit bare JSON.
raw = result.content.strip()
if raw.startswith("```"):
first_nl = raw.find("\n")
if first_nl != -1:
raw = raw[first_nl + 1:]
if raw.rstrip().endswith("```"):
raw = raw.rstrip()[:-3].rstrip()
raw = raw.strip()
try:
parsed = json.loads(raw)
except json.JSONDecodeError:
log.warning("review.parse_failed", preview=result.content[:200])
return Verdict(clean=False, reason="reviewer returned non-JSON",
cost_usd=result.cost_usd)
clean = parsed.get("clean")
reason = parsed.get("reason") or ""
if not isinstance(clean, bool):
return Verdict(clean=False, reason="reviewer omitted bool 'clean'",
cost_usd=result.cost_usd)
return Verdict(clean=clean, reason=str(reason)[:200], cost_usd=result.cost_usd)