{"i":18,"slug":"json-schema-vs-instructions","chart":{"id":"structured-output-outcomes","title":"What each call produced: strict pass, format miss, wrong values or error","subtitle":"Counts of calls per configuration; the three prompts pooled","kind":"stacked-bar","unit":"count","yLabel":"Calls","series":{"$k":["name","points"],"$r":[["Strict pass",{"$k":["label","value","n"],"$r":[["Claude Haiku 4.5 (instructions) · Claude Code",0,24],["Claude Haiku 4.5 (JSON schema) · Claude Code",18,24],["Claude Sonnet 5.5 (instructions) · Claude Code",12,12],["Claude Sonnet 5.5 (JSON schema) · Claude Code",12,12],["GPT-6.1 Sol (low, instructions) · Codex CLI",12,12],["GPT-6.1 Sol (low, JSON schema) · Codex CLI",12,12]]}],["Format miss",{"$k":["label","value","n"],"$r":[["Claude Haiku 4.5 (instructions) · Claude Code",17,24],["Claude Haiku 4.5 (JSON schema) · Claude Code",0,24],["Claude Sonnet 5.5 (instructions) · Claude Code",0,12],["Claude Sonnet 5.5 (JSON schema) · Claude Code",0,12],["GPT-6.1 Sol (low, instructions) · Codex CLI",0,12],["GPT-6.1 Sol (low, JSON schema) · Codex CLI",0,12]]}],["Wrong values",{"$k":["label","value","n"],"$r":[["Claude Haiku 4.5 (instructions) · Claude Code",7,24],["Claude Haiku 4.5 (JSON schema) · Claude Code",6,24],["Claude Sonnet 5.5 (instructions) · Claude Code",0,12],["Claude Sonnet 5.5 (JSON schema) · Claude Code",0,12],["GPT-6.1 Sol (low, instructions) · Codex CLI",0,12],["GPT-6.1 Sol (low, JSON schema) · Codex CLI",0,12]]}],["Error",{"$k":["label","value","n"],"$r":[["Claude Haiku 4.5 (instructions) · Claude Code",0,24],["Claude Haiku 4.5 (JSON schema) · Claude Code",0,24],["Claude Sonnet 5.5 (instructions) · Claude Code",0,12],["Claude Sonnet 5.5 (JSON schema) · Claude Code",0,12],["GPT-6.1 Sol (low, instructions) · Codex CLI",0,12],["GPT-6.1 Sol (low, JSON schema) · Codex CLI",0,12]]}]]},"note":"Counts of calls, not rates; the pass-rate chart carries the same results with 95% intervals. Format miss: the right answer inside a code fence or prose. Wrong values: any other completed reply, with a wrong value, key or type (a reply that sits in a code fence and also has a wrong value is counted here). Error: the call did not complete.","sourceIds":["agent-structured-output"]}}