encode

name	encode
description	Translate constraint problems into SMT-LIB2 or Z3 Python API code. Handles common problem classes including scheduling, graph coloring, arithmetic puzzles, and verification conditions.

Given a problem description (natural language, pseudocode, or a partial formulation), produce a complete, syntactically valid SMT-LIB2 encoding or Z3 Python script. The encoding should declare all variables, assert all constraints, and include the appropriate check-sat / get-model commands.

Step 1: Identify the problem class

Action: Determine the SMT theory and variable sorts required by the problem description.

Expectation: A clear mapping from the problem to one of the supported theories (LIA, LRA, QF_BV, etc.).

Result: If the theory is identified, proceed to Step 2. If the problem spans multiple theories, select the appropriate combined logic.

Problem class	Theory	Typical sorts
Integer arithmetic	LIA / NIA	Int
Real arithmetic	LRA / NRA	Real
Bitvector operations	QF_BV	(_ BitVec N)
Arrays and maps	QF_AX	(Array Int Int)
Strings and regex	QF_S	String, RegLan
Uninterpreted functions	QF_UF	custom sorts
Mixed theories	AUFLIA, etc.	combination

Step 2: Generate the encoding

Action: Invoke encode.py with the problem description and desired output format.

Expectation: The script produces a complete SMT-LIB2 file or Z3 Python script with all declarations, constraints, and check-sat commands.

Result: For smtlib2 format: pass the output to solve. For python format: execute the script directly. Proceed to Step 3 for validation.

python3 scripts/encode.py --problem "Find integers x, y such that x^2 + y^2 = 25 and x > 0" --format smtlib2
python3 scripts/encode.py --problem "Schedule 4 tasks on 2 machines minimizing makespan" --format python

Step 3: Validate the encoding

Action: The script runs a syntax check by piping the output through z3 -in in parse-only mode.

Expectation: No parse errors. If errors occur, the offending line is reported.

Result: On success: the encoding is ready for solve, prove, or optimize. On parse error: fix the reported line and re-run.

Parameters

Parameter	Type	Required	Default	Description
problem	string	yes		problem description
format	string	no	smtlib2	output format: smtlib2 or python
output	path	no	stdout	write to file instead of stdout
validate	flag	no	on	run syntax check on the output
debug	flag	no	off	verbose tracing
db	path	no	.z3-agent/z3agent.db	logging database