- Changed all 50 org file :tangle targets from ../lisp/ to ~/.local/share/passepartout/lisp/ (XDG data dir) - Removed 49 generated .lisp files from project lisp/ directory - Removed tests/system-integration-tests.lisp (generated) - Removed lisp/*.fasl (compiled, stale) - Updated core-manifest.org to tangle .asd to XDG root - Remapped quicklisp symlink: local-projects/passepartout → XDG TUI fixes in channel-tui-main.org: - Removed with-raw-terminal (stty raw breaks fd 0 reads in this SBCL) - Use cat subprocess + pipe for keyboard input (via :input :interactive) - Blocking read-char on pipe with with-timeout 0.1s for daemon processing - Key events queued via drain-queue alongside daemon messages - Full dialog key routing (Escape, Up/Down, Enter, filters, Backspace) - SIGWINCH resize handling - Post-handshake backend-size re-query - Daemon version in status bar (was v0.5.0 hardcoded) - Handshake version stored in state, no add-msg - :daemon-version and :size-queried in state plist - view-status uses draw-rect for background - Test section gated with #+passepartout-tests
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Token Economics — caching, budget, and cost wiring
Architectural Intent
Token economics transforms the architecture's theoretical cost advantage into operational reality. Three subsystems work together:
Prompt prefix caching— the IDENTITY+TOOLS portion of the system prompt is static across calls (changes only on skill load or identity config). Hashing and caching it avoids retransmitting ~500-1500 tokens per call.Incremental context assembly— the CONTEXT section is only regenerated when the foveal focus, scope, or memory state changes. Heartbeat ticks and tool-output feedback produce no context change, so assembly is skipped, saving ~200-800 tokens per heartbeat.Token budget enforcement— when the total prompt exceedsCONTEXT_MAX_TOKENS(default 16384), the system progressively trims less-essential sections (logs first, then standing mandates, then peripheral context).
These functions are called from think() via fboundp guards, keeping
core-reason thin while enabling token economics as a hot-loadable skill.
Depends on: tokenizer.lisp, cost-tracker.lisp
v0.8.0 — Context Usage for Sidebar
The sidebar's Context gauge needs a single integer: 0-100 representing
how much of the token budget is consumed. context-usage-percentage
computes this from *context-cache*'s stored token counts and
CONTEXT_MAX_TOKENS (or the model's context limit from tokenizer).
The function is a thin wrapper (8 lines): read the most recent context
assembly's token count from ~*context-cache*, divide by the budget,
multiply by 100, clamp to [0, 100]. Called from core-act.org's :tui
actuator via fboundp guard. Degrades gracefully to nil when
token-economics is not loaded.
Contract
- (prompt-prefix-cached assistant-name identity-content feedback mandates-text tool-belt):
Build the IDENTITY+TOOLS system prompt prefix. Uses
sxhashon the inputs to detect changes. Returns the cached string when unchanged. - (context-assemble-cached context sensor): Incrementally assemble awareness
context. Skips assembly entirely for
:heartbeat/:delegationsensors. Returns cached context when foveal-id, scope, and memory timestamp are unchanged. Falls back to[Awareness skill not loaded]whencontext-assemble-global-awarenessis notfboundp. - (enforce-token-budget prefix ctxt logs user prompt mandates &optional max): Enforce per-call token budget via progressive trimming: L1: truncate logs to last 5 lines L2: drop standing mandates L3: downgrade context to single-line summary Returns (values trimmed-prefix trimmed-ctxt trimmed-logs trimmed-user trimmed-mandates).
- (token-economics-initialize): zeroes the cache state at daemon boot.
- (context-usage-percentage): returns integer 0-100 representing
current token budget consumption from
*context-cache*. Clamped. Returns nil when no context cache data is available. Consumed by the TUI actuator for the sidebar Context gauge (v0.8.0).
Implementation
Package context
(in-package :passepartout)
Cache state
(defvar *prompt-prefix-cache* (cons nil "")
"Prompt prefix cache: (sxhash . cached-string). Rebuilt when IDENTITY or TOOLS change.")
(defvar *context-cache* (list :foveal-id nil :scope nil :memory-timestamp 0 :rendered ""
:identity-tokens 0 :tool-tokens 0 :context-tokens 0
:log-tokens 0 :config-tokens 0 :time-tokens 0)
"Context assembly cache: metadata + last rendered context string.")
Contract 1: prompt prefix caching
(defun prompt-prefix-cached (assistant-name identity-content feedback mandates-text tool-belt)
"Build the static IDENTITY+TOOLS system prompt prefix.
Uses sxhash on inputs to detect changes; returns cached string on cache hit."
(let* ((hash-key (sxhash (list assistant-name identity-content feedback mandates-text tool-belt)))
(cached-hash (car *prompt-prefix-cache*))
(cached-str (cdr *prompt-prefix-cache*)))
(if (and cached-str (> (length cached-str) 0) (= hash-key cached-hash))
cached-str
(let ((new-prefix (format nil "IDENTITY: ~a~a~a~a~%~%TOOLS:~%~a"
assistant-name identity-content feedback
(if (and mandates-text (> (length mandates-text) 0))
(concatenate 'string (string #\Newline) mandates-text)
"")
tool-belt)))
(setf (car *prompt-prefix-cache*) hash-key
(cdr *prompt-prefix-cache*) new-prefix)
new-prefix))))
Contract 2: incremental context assembly
(defun context-assemble-cached (context sensor)
"Incrementally assemble awareness context.
Skips assembly for heartbeat/delegation sensors.
Uses cache when foveal, scope, and memory timestamp are unchanged."
(when (member sensor '(:heartbeat :delegation))
(return-from context-assemble-cached nil))
(unless (fboundp 'context-assemble-global-awareness)
(return-from context-assemble-cached "[Awareness skill not loaded]"))
(let* ((foveal-id (getf context :foveal-focus))
(scope (if (and (boundp '*scope-resolver*)
*scope-resolver*)
(funcall *scope-resolver*)
nil))
(mem-ts (hash-table-count *memory-store*))
(cache-foveal (getf *context-cache* :foveal-id))
(cache-scope (getf *context-cache* :scope))
(cache-ts (getf *context-cache* :memory-timestamp))
(cache-rendered (getf *context-cache* :rendered)))
(if (and (equal foveal-id cache-foveal)
(eq scope cache-scope)
(= mem-ts cache-ts)
cache-rendered
(> (length cache-rendered) 0))
cache-rendered
(let ((rendered (funcall (symbol-function 'context-assemble-global-awareness))))
(setf (getf *context-cache* :foveal-id) foveal-id
(getf *context-cache* :scope) scope
(getf *context-cache* :memory-timestamp) mem-ts
(getf *context-cache* :rendered) rendered)
rendered))))
Contract 3: token budget enforcement
(defun enforce-token-budget (prefix context-text logs-text user-prompt mandates-text
&optional (max-tokens nil))
"Enforce per-call token budget via progressive trimming.
Returns (values prefix context-text logs-text user-prompt mandates-text)
with trimmed sections."
(let ((max (or max-tokens
(ignore-errors
(parse-integer (uiop:getenv "CONTEXT_MAX_TOKENS")))
16384)))
(labels ((ct (s) (if (fboundp 'count-tokens)
(funcall (symbol-function 'count-tokens) s)
(ceiling (length s) 4)))
(total-tokens (p c l u m)
(+ (ct p)
(if c (ct c) 0)
(ct l)
(ct u)
(if m (ct m) 0))))
(let ((total (total-tokens prefix context-text logs-text user-prompt mandates-text)))
(when (> total max)
(log-message "TOKEN BUDGET: ~d tokens exceeds max ~d, trimming..."
total max)
;; L1: truncate logs to last 5 lines
(let* ((log-lines (uiop:split-string logs-text :separator '(#\Newline)))
(trimmed (if (> (length log-lines) 5)
(format nil "~{~a~^~%~}" (last log-lines 5))
logs-text)))
(setf total (total-tokens prefix context-text trimmed user-prompt mandates-text)
logs-text trimmed)
(when (> total max)
;; L2: drop standing mandates
(setf total (total-tokens prefix context-text logs-text user-prompt nil)
mandates-text nil)
(when (> total max)
;; L3: downgrade context to summary
(let ((ctxt-lines (uiop:split-string (or context-text "") :separator '(#\Newline))))
(setf context-text
(format nil "[Context trimmed: ~d items]" (length ctxt-lines)))))))))
(values prefix context-text logs-text user-prompt mandates-text))))
Contract 4: initialization
(defun token-economics-initialize ()
"Zero cache state at daemon boot."
(setf (car *prompt-prefix-cache*) nil
(cdr *prompt-prefix-cache*) ""
(getf *context-cache* :foveal-id) nil
(getf *context-cache* :scope) nil
(getf *context-cache* :memory-timestamp) 0
(getf *context-cache* :rendered) ""))
Contract 5: context usage percentage (v0.8.0)
(defun context-usage-percentage ()
"Returns integer 0-100: current token budget consumption.
Returns nil when no context cache data is available."
(let* ((limit (or (ignore-errors
(parse-integer (uiop:getenv "CONTEXT_MAX_TOKENS")))
16384))
(tokens (+ (or (getf *context-cache* :identity-tokens) 0)
(or (getf *context-cache* :tool-tokens) 0)
(or (getf *context-cache* :context-tokens) 0)
(or (getf *context-cache* :log-tokens) 0)
(or (getf *context-cache* :config-tokens) 0)
(or (getf *context-cache* :time-tokens) 0))))
(if (> tokens 0)
(min 100 (floor (* 100 tokens) limit))
nil)))
Test Suite
(eval-when (:compile-toplevel :load-toplevel :execute)
(ql:quickload :fiveam :silent t))
(defpackage :passepartout-token-economics-tests
(:use :cl :fiveam :passepartout)
(:export #:token-economics-suite))
(in-package :passepartout-token-economics-tests)
(def-suite token-economics-suite
:description "Prompt prefix caching, incremental context, token budget")
(in-suite token-economics-suite)
(test test-prompt-prefix-cached-identity
"Contract 1: prompt-prefix-cached includes identity-content when provided."
(setf (car passepartout::*prompt-prefix-cache*) nil
(cdr passepartout::*prompt-prefix-cache*) "")
(let ((prefix (passepartout::prompt-prefix-cached
"Agent" "### Mode: concise" "" nil "No tools")))
(is (stringp prefix))
(is (search "IDENTITY" prefix))
(is (search "Mode: concise" prefix))
(is (search "TOOLS" prefix))))
(test test-prompt-prefix-cached-builds
"Contract 1: prompt-prefix-cached returns a string containing IDENTITY."
(setf (car passepartout::*prompt-prefix-cache*) nil
(cdr passepartout::*prompt-prefix-cache*) "")
(let ((prefix (passepartout::prompt-prefix-cached "Agent" "" "" nil "No tools")))
(is (stringp prefix))
(is (search "IDENTITY" prefix))
(is (search "TOOLS" prefix))))
(test test-prompt-prefix-cached-hits
"Contract 1: second call with same inputs returns cached result."
(setf (car passepartout::*prompt-prefix-cache*) nil
(cdr passepartout::*prompt-prefix-cache*) "")
(let ((p1 (passepartout::prompt-prefix-cached "Agent" "" "" nil "No tools"))
(p2 (passepartout::prompt-prefix-cached "Agent" "" "" nil "No tools")))
(is (string= p1 p2))))
(test test-prompt-prefix-cached-miss
"Contract 1: different inputs rebuild the cache."
(setf (car passepartout::*prompt-prefix-cache*) nil
(cdr passepartout::*prompt-prefix-cache*) "")
(let ((p1 (passepartout::prompt-prefix-cached "Agent" "" "" nil "No tools"))
(p2 (passepartout::prompt-prefix-cached "Bot" "" "" nil "No tools")))
(is (not (string= p1 p2)))
(is (search "Bot" p2))))
(test test-context-assemble-cached-skips-heartbeat
"Contract 2: heartbeat sensors skip context assembly, return nil."
(let ((result (passepartout::context-assemble-cached
'(:foveal-focus "id1") :heartbeat)))
(is (null result))))
(test test-context-assemble-cached-skips-delegation
"Contract 2: delegation sensors also skip assembly."
(let ((result (passepartout::context-assemble-cached
'(:foveal-focus "id1") :delegation)))
(is (null result))))
(test test-context-assemble-cached-non-skip
"Contract 2: user-input sensors attempt assembly (fails gracefully without awareness)."
(let ((result (passepartout::context-assemble-cached
'(:foveal-focus "id1") :user-input)))
(is (stringp result))
(is (> (length result) 0))))
(test test-enforce-token-budget-passthrough
"Contract 3: under-budget prompts pass through unchanged."
(multiple-value-bind (p c l u m)
(passepartout::enforce-token-budget "hi" "ctxt" "log" "user" nil 100000)
(is (string= "hi" p))
(is (string= "ctxt" c))
(is (string= "log" l))
(is (string= "user" u))
(is (null m))))
(test test-enforce-token-budget-trims
"Contract 3: over-budget prompts get trimmed."
(let ((big-prefix (make-string 20000 :initial-element #\x)))
(multiple-value-bind (p c l u m)
(passepartout::enforce-token-budget big-prefix "ctxt" "logs\nlogs\nlogs\nlogs\nlogs\nlogs\nlogs" "user" nil 10)
(declare (ignore p l u m))
;; The prefix itself exceeds the tiny 10-token budget, so everything gets trimmed
(is (or (stringp c) (null c)))
(is (search "[Context trimmed" (or c ""))))))
(test test-token-economics-initialize
"Contract 4: initialize zeroes all cache state."
(setf (car passepartout::*prompt-prefix-cache*) 12345
(cdr passepartout::*prompt-prefix-cache*) "stale")
(setf (getf passepartout::*context-cache* :rendered) "stale context")
(passepartout::token-economics-initialize)
(is (null (car passepartout::*prompt-prefix-cache*)))
(is (string= "" (cdr passepartout::*prompt-prefix-cache*)))
(is (string= "" (getf passepartout::*context-cache* :rendered))))
(in-package :passepartout-token-economics-tests)
(test test-context-usage-percentage
"Contract 5: context-usage-percentage returns integer 0-100."
;; Set up a cache with known token counts
(let* ((ctx passepartout::*context-cache*)
(limit (or (ignore-errors (parse-integer (uiop:getenv "CONTEXT_MAX_TOKENS")))
16384)))
(setf (getf ctx :identity-tokens) 1000
(getf ctx :tool-tokens) 500
(getf ctx :context-tokens) 2000
(getf ctx :log-tokens) 800
(getf ctx :config-tokens) 200
(getf ctx :time-tokens) 100)
(let ((pct (passepartout::context-usage-percentage)))
(is (integerp pct))
(is (<= 0 pct 100)))))
(test test-context-usage-percentage-empty-cache
"Contract 5: context-usage-percentage returns nil with no cache data."
(let ((saved-ctx (copy-list passepartout::*context-cache*)))
(unwind-protect
(progn
(setf (getf passepartout::*context-cache* :identity-tokens) nil
(getf passepartout::*context-cache* :tool-tokens) nil
(getf passepartout::*context-cache* :context-tokens) nil
(getf passepartout::*context-cache* :log-tokens) nil
(getf passepartout::*context-cache* :config-tokens) nil
(getf passepartout::*context-cache* :time-tokens) nil)
(is (null (passepartout::context-usage-percentage))))
(setf passepartout::*context-cache* saved-ctx))))