TruncationCompactionStrategy Class
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
A compaction strategy that removes the oldest non-system message groups, keeping at least MinimumPreservedGroups most-recent groups intact.
public sealed class TruncationCompactionStrategy : Microsoft.Agents.AI.Compaction.CompactionStrategytype TruncationCompactionStrategy = class
inherit CompactionStrategyPublic NotInheritable Class TruncationCompactionStrategy
Inherits CompactionStrategy- Inheritance
Remarks
This strategy preserves system messages and removes the oldest non-system message groups first. It respects atomic group boundaries — an assistant message with tool calls and its corresponding tool result messages are always removed together.
MinimumPreservedGroups is a hard floor: even if the Target has not been reached, compaction will not touch the last MinimumPreservedGroups non-system groups.
The CompactionTrigger controls when compaction proceeds. Use CompactionTriggers for common trigger conditions such as token or group thresholds.
Constructors
| Name | Description |
|---|---|
| TruncationCompactionStrategy(CompactionTrigger, Int32, CompactionTrigger) |
Initializes a new instance of the TruncationCompactionStrategy class. |
Fields
| Name | Description |
|---|---|
| DefaultMinimumPreserved |
The default minimum number of most-recent non-system groups to preserve. |
Properties
| Name | Description |
|---|---|
| MinimumPreservedGroups |
Gets the minimum number of most-recent non-system message groups that are always preserved. This is a hard floor that compaction cannot exceed, regardless of the target condition. |
| Target |
Gets the target predicate that controls when compaction stops.
Strategies re-evaluate this after each incremental exclusion and stop when it returns |
| Trigger |
Gets the trigger predicate that controls when compaction proceeds. (Inherited from CompactionStrategy) |
Methods
| Name | Description |
|---|---|
| CompactAsync(CompactionMessageIndex, ILogger, CancellationToken) |
Evaluates the Trigger and, when it fires, delegates to CompactCoreAsync(CompactionMessageIndex, ILogger, CancellationToken) and reports compaction metrics. (Inherited from CompactionStrategy) |
| CompactCoreAsync(CompactionMessageIndex, ILogger, CancellationToken) |
Applies the strategy-specific compaction logic to the specified message index. (Inherited from CompactionStrategy) |
Extension Methods
| Name | Description |
|---|---|
| AsChatReducer(CompactionStrategy) |
Returns an IChatReducer that applies this CompactionStrategy to reduce a list of messages. |