Function SessionTaskKey

internal/llm/sessionkey.go:65–81

SessionTaskKey derives the prompt-cache affinity key for one task conversation within a session. Prompt caches match on prefixes, and OCR's task types (plan, main tool-loop, compression, dedup, ...) use unrelated prompts — routing a whole run under one key would pin every concurrent per-file convers

(sessionKey, taskType, scope string)

// within the provider-safe limit. The shortened component is only a cache
// routing hint; the complete session ID remains unchanged in persisted state.
func SessionTaskKey(sessionKey, taskType, scope string) string {
	if len(sessionKey) > sessionTaskKeySessionPrefixLength {
		sessionKey = sessionKey[:sessionTaskKeySessionPrefixLength]
	}
	if len(taskType) > maxSessionTaskKeyTaskTypeLength {
		taskType = taskType[:maxSessionTaskKeyTaskTypeLength]
	}

	if taskType == "" && scope == "" {
		return sessionKey
	}
	if scope == "" {
		return sessionKey + "-" + taskType
	}
	sum := sha256.Sum256([]byte(scope))
	return fmt.Sprintf("%s-%s-%x", sessionKey, taskType, sum[:8])
}

// SessionKeyFromContext returns the session key carried by ctx, or "" when
// none was set.