In-Context State Management

This document describes how the OpenProse VM tracks execution state using structured narration in the conversation history. This is one of two state management approaches (the other being file-based state in filesystem.md).

Overview

In-context state uses text-prefixed markers to persist state within the conversation. The VM "thinks aloud" about execution—what you say becomes what you remember.

Key principle: Your conversation history IS the VM's working memory.

When to Use In-Context State

In-context state is appropriate for:

Factor	In-Context	Use File-Based Instead
Statement count	< 30 statements	>= 30 statements
Parallel branches	< 5 concurrent	>= 5 concurrent
Imported programs	0-2 imports	>= 3 imports
Nested depth	<= 2 levels	> 2 levels
Expected duration	< 5 minutes	>= 5 minutes

Announce your state mode at program start:

OpenProse Program Start
   State mode: in-context (program is small, fits in context)

The Narration Protocol

Use text-prefixed markers for each state change:

Marker	Category	Usage
[Program]	Program	Start, end, definition collection
[Position]	Position	Current statement being executed
[Binding]	Binding	Variable assignment or update
[Input]	Input	Receiving inputs from caller
[Output]	Output	Producing outputs for caller
[Import]	Import	Fetching and invoking imported programs
[Success]	Success	Session or block completion
[Warning]	Error	Failures and exceptions
[Parallel]	Parallel	Entering, branch status, joining
[Loop]	Loop	Iteration, condition evaluation
[Pipeline]	Pipeline	Stage progress
[Try]	Error handling	Try/catch/finally
[Flow]	Flow	Condition evaluation results
[Frame+]	Call Stack	Push new frame (block invocation)
[Frame-]	Call Stack	Pop frame (block completion)

Narration Patterns by Construct

Session Statements

[Position] Executing: session "Research the topic"
   [Task tool call]
[Success] Session complete: "Research found that..."
[Binding] let research = <result>

Parallel Blocks

[Parallel] Entering parallel block (3 branches, strategy: all)
   - security: pending
   - perf: pending
   - style: pending
   [Multiple Task calls]
[Parallel] Parallel complete:
   - security = "No vulnerabilities found..."
   - perf = "Performance is acceptable..."
   - style = "Code follows conventions..."
[Binding] security, perf, style bound

Loop Blocks

[Loop] Starting loop until **task complete** (max: 5)

[Loop] Iteration 1 of max 5
   [Position] session "Work on task"
   [Success] Session complete
   [Loop] Evaluating: **task complete**
   [Flow] Not satisfied, continuing

[Loop] Iteration 2 of max 5
   [Position] session "Work on task"
   [Success] Session complete
   [Loop] Evaluating: **task complete**
   [Flow] Satisfied!

[Loop] Loop exited: condition satisfied at iteration 2

Error Handling

[Try] Entering try block
[Position] session "Risky operation"
[Warning] Session failed: connection timeout
[Binding] err = {message: "connection timeout"}
[Try] Executing catch block
[Position] session "Handle error" with context: err
[Success] Recovery complete
[Try] Executing finally block
[Position] session "Cleanup"
[Success] Cleanup complete

Variable Bindings

[Binding] let research = "AI safety research covers..." (mutable)
[Binding] const config = {model: "opus"} (immutable)
[Binding] research = "Updated research..." (reassignment, was: "AI safety...")

Input/Output Bindings

[Input] Inputs received:
   topic = "quantum computing" (from caller)
   depth = "deep" (from caller)

[Output] output findings = "Research shows..." (will return to caller)
[Output] output sources = ["arxiv:2401.1234", ...] (will return to caller)

Block Invocation and Call Stack

Track block invocations with frame markers:

[Position] do process(data, 5)
[Frame+] Entering block: process (execution_id: 1, depth: 1)
   Arguments: chunk=data, depth=5

   [Position] session "Split into parts"
      [Task tool call]
   [Success] Session complete
   [Binding] let parts = <result> (execution_id: 1)

   [Position] do process(parts[0], 4)
   [Frame+] Entering block: process (execution_id: 2, depth: 2)
      Arguments: chunk=parts[0], depth=4
      Parent: execution_id 1

      [Position] session "Split into parts"
         [Task tool call]
      [Success] Session complete
      [Binding] let parts = <result> (execution_id: 2)  # Shadows parent's 'parts'

      ... (continues recursively)

   [Frame-] Exiting block: process (execution_id: 2)

   [Position] session "Combine results"
      [Task tool call]
   [Success] Session complete

[Frame-] Exiting block: process (execution_id: 1)

Key points:

Each [Frame+] must have a matching [Frame-]
execution_id uniquely identifies each invocation
depth shows call stack depth (1 = first level)
Bindings include (execution_id: N) to indicate scope
Nested frames show Parent: execution_id N for the scope chain

Scoped Binding Narration

When inside a block invocation, always include the execution_id:

[Binding] let result = "computed value" (execution_id: 43)

For variable resolution across scopes:

[Binding] Resolving 'config': found in execution_id 41 (parent scope)

Program Imports

[Import] Importing: @alice/research
   Fetching from: https://p.prose.md/@alice/research
   Inputs expected: [topic, depth]
   Outputs provided: [findings, sources]
   Registered as: research

[Import] Invoking: research(topic: "quantum computing")
   [Input] Passing inputs:
      topic = "quantum computing"

   [... imported program execution ...]

   [Output] Received outputs:
      findings = "Quantum computing uses..."
      sources = ["arxiv:2401.1234"]

[Import] Import complete: research
[Binding] result = { findings: "...", sources: [...] }

Context Serialization

In-context state passes values, not references. This is the key difference from file-based and PostgreSQL state. The VM holds binding values directly in conversation history.

When passing context to sessions, format appropriately:

Context Size	Strategy
< 2000 chars	Pass verbatim
2000-8000 chars	Summarize to key points
> 8000 chars	Extract essentials only

Format:

Context provided:
---
research: "Key findings about AI safety..."
analysis: "Risk assessment shows..."
---

Limitation: In-context state cannot support RLM-style "environment as variable" patterns where agents query arbitrarily large bindings. For programs with large intermediate values, use file-based or PostgreSQL state instead.

Complete Execution Trace Example

prose

agent researcher:
  model: sonnet

let research = session: researcher
  prompt: "Research AI safety"

parallel:
  a = session "Analyze risk A"
  b = session "Analyze risk B"

loop until **analysis complete** (max: 3):
  session "Synthesize"
    context: { a, b, research }

Narration:

[Program] Program Start
   Collecting definitions...
   - Agent: researcher (model: sonnet)

[Position] Statement 1: let research = session: researcher
   Spawning with prompt: "Research AI safety"
   Model: sonnet
   [Task tool call]
[Success] Session complete: "AI safety research covers alignment..."
[Binding] let research = <result>

[Position] Statement 2: parallel block
[Parallel] Entering parallel (2 branches, strategy: all)
   [Task: "Analyze risk A"] [Task: "Analyze risk B"]
[Parallel] Parallel complete:
   - a = "Risk A: potential misalignment..."
   - b = "Risk B: robustness concerns..."
[Binding] a, b bound

[Position] Statement 3: loop until **analysis complete** (max: 3)
[Loop] Starting loop

[Loop] Iteration 1 of max 3
   [Position] session "Synthesize" with context: {a, b, research}
   [Task with serialized context]
   [Success] Result: "Initial synthesis shows..."
   [Loop] Evaluating: **analysis complete**
   [Flow] Not satisfied (synthesis is preliminary)

[Loop] Iteration 2 of max 3
   [Position] session "Synthesize" with context: {a, b, research}
   [Task with serialized context]
   [Success] Result: "Comprehensive analysis complete..."
   [Loop] Evaluating: **analysis complete**
   [Flow] Satisfied!

[Loop] Loop exited: condition satisfied at iteration 2

[Program] Program Complete

State Categories

The VM must track these state categories in narration:

Category	What to Track	Example
Import Registry	Imported programs and aliases	`research: @alice/research`
Agent Registry	All agent definitions	`researcher: {model: sonnet, prompt: "..."}`
Block Registry	All block definitions (hoisted)	`review: {params: [topic], body: [...]}`
Input Bindings	Inputs received from caller	`topic = "quantum computing"`
Output Bindings	Outputs to return to caller	`findings = "Research shows..."`
Variable Bindings	Name -> value mapping (with execution_id)	`result = "..." (execution_id: 3)`
Variable Mutability	Which are `let` vs `const` vs `output`	`research: let, findings: output`
Execution Position	Current statement index	Statement 3 of 7
Loop State	Counter, max, condition	Iteration 2 of max 5
Parallel State	Branches, results, strategy	`{a: complete, b: pending}`
Error State	Exception, retry count	Retry 2 of 3, error: "timeout"
Call Stack	Stack of execution frames	See below

Call Stack State

For block invocations, track the full call stack:

[CallStack] Current stack (depth: 3):
   execution_id: 5 | block: process | depth: 3 | status: executing
   execution_id: 3 | block: process | depth: 2 | status: waiting
   execution_id: 1 | block: process | depth: 1 | status: waiting

Each frame tracks:

execution_id: Unique ID for this invocation
block: Name of the block
depth: Position in call stack
status: executing, waiting, or completed

Independence from File-Based State

In-context state and file-based state (filesystem.md) are independent approaches. You choose one or the other based on program complexity.

In-context: State lives in conversation history
File-based: State lives in .prose/runs/{id}/

They are not designed to be complementary—pick the appropriate mode at program start.

Summary

In-context state management:

Uses text-prefixed markers to track state changes
Persists state in conversation history
Is appropriate for smaller, simpler programs
Requires consistent narration throughout execution
Makes state visible in the conversation itself

The narration protocol ensures that the VM can recover its execution state by reading its own prior messages. What you say becomes what you remember.