> ## Documentation Index > Fetch the complete documentation index at: https://langchain-5e9cc07a-preview-docsby-1791319236-3be7a15.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Migrate thread methods to SmithDB > Migrate the LangSmith SDK thread methods to their SmithDB-backed equivalents. These methods query threads and list the traces inside a thread. For deprecation dates, minimum SDK versions, and the agent prompt that applies to every method, see [Migrate to SmithDB-backed SDK methods](/langsmith/smithdb-sdk-migration). ## Threads: query Query threads within a project, with cursor-based pagination. Returns threads matching the given time range and optional filter. ### Main changes #### Method name | Before | After | | - | - | | `client.list_threads()` | `client.threads.query()` | `client.threads.query()` is now async. Call it with `await`. See the [reference](https://reference.langchain.com/python/langsmith/_openapi_client/resources/threads/ThreadsResource/query) for the full parameter and field list. | Before | After | | - | - | | `client.listThreads()` | `client.threads.query()` | See the [reference](https://reference.langchain.com/javascript/langsmith/_openapi_client/Langsmith/Threads/query) for the full parameter and field list. Java never had a dedicated thread-listing method. The closest legacy equivalent is the generic run query, manually grouped by the `thread_id` metadata convention. | Before | After | | - | - | | `client.runs().query()` (generic, grouped client-side) | `client.threads().query()` | See the [reference](https://javadoc.io/doc/com.langchain.smith/langsmith-java/latest/com/langchain/smith/services/blocking/ThreadService.html) for the full parameter list. Go never had a dedicated thread-listing method. The closest legacy equivalent is the generic run query, manually grouped by the `thread_id` metadata convention. | Before | After | | - | - | | `client.Runs.Query()` (generic, grouped client-side) | `client.Threads.Query()` | See the [reference](https://pkg.go.dev/github.com/langchain-ai/langsmith-go#ThreadService.QueryAutoPaging) for the full parameter list. | Before | After | | - | - | | `POST /api/v1/runs/query` (`is_root=true`, grouped client-side) | `POST /api/v2/threads/query` | See the [API doc](/langsmith/smith-api/threads/query-threads) for the full parameter and field list. #### Query parameters | Before (`list_threads`) | After (`threads.query`) | Notes | | - | - | - | | `project_id` XOR `project_name` | `project_id` | the new method takes only the UUID; resolve a name via `aread_project()` first, same pattern as `Runs: query` | | `start_time` (defaults to 1 day ago) | `min_start_time` + `max_start_time` | Optional; default to a 1-day window ending now, same as `start_time` | | `offset` + `limit` | `cursor` + `page_size` | Offset pagination replaced by cursor pagination | | `filter` (evaluated against runs) | `filter` | Same syntax; now evaluated against each thread's root run | | Before (`listThreads`) | After (`threads.query`) | Notes | | - | - | - | | `projectId` XOR `projectName` | `project_id` | the new method takes only the UUID; resolve a name via `readProject()` first | | `startTime` (defaults to 1 day ago) | `min_start_time` + `max_start_time` | Optional; default to a 1-day window ending now, same as `startTime` | | `offset` + `limit` | `cursor` + `page_size` | Offset pagination replaced by cursor pagination | | `filter` | `filter` | Same syntax; now evaluated against each thread's root run | No query parameters to map. There was no dedicated method. The old approach used the generic run query (`is_root=true`, manual grouping by `thread_id` metadata). `threads().query()` takes `projectId`, `minStartTime`, `maxStartTime` (both optional, defaulting to a 1-day window ending now), `filter`, `pageSize`, `cursor`. No query parameters to map. There was no dedicated method. The old approach used the generic run query (`IsRoot: true`, manual grouping by `thread_id` metadata). `Threads.Query()` takes `ProjectID`, `MinStartTime`, `MaxStartTime` (both optional, defaulting to a 1-day window ending now), `Filter`, `PageSize`, `Cursor`. `POST /api/v2/threads/query` body fields: `project_id`, `min_start_time` (optional), `max_start_time` (optional), `filter`, `page_size`, `cursor` (all `snake_case`). `min_start_time`/`max_start_time` default to a 1-day window ending now when omitted. #### Response fields Python's legacy `ListThreadsItem` only has `thread_id`, `runs` (full embedded `Run[]`), `count`, `min_start_time`, `max_start_time`. It has no token/cost/latency/feedback fields at all. The new `Thread` never embeds the full run list (that is what `threads.list_traces` is for) but adds real `feedback_stats`, `latency_p50`/`latency_p99`, cost/token sums with per-category `_details`, `first_trace_id`/`last_trace_id`, `first_inputs`/`last_outputs` previews, `last_error`, `num_errored_turns`. | Before (legacy `ListThreadsItem`) | After (new `Thread`) | Notes | | - | - | - | | `thread_id` | `thread_id` | Unchanged | | `runs` (full embedded `Run[]`) | *(not available)* | Use `threads.list_traces` for per-trace detail | | `count` | `count` | Unchanged | | `min_start_time` | `min_start_time` | Unchanged | | `max_start_time` | `max_start_time` | Unchanged | | *(not available)* | `start_time` | New: a reference start time for this row, for example for sorting | | *(not available)* | `trace_id` | New: a representative root trace UUID, for example for deep links | | *(not available)* | `first_trace_id`, `last_trace_id` | New: chronologically first/last trace UUID in the query window | | *(not available)* | `first_inputs`, `last_outputs` | New: truncated previews from the first/last trace | | *(not available)* | `last_error` | New | | *(not available)* | `num_errored_turns` | New | | *(not available)* | `latency_p50`, `latency_p99` | New | | *(not available)* | `total_tokens`, `total_cost` | New | | *(not available)* | `total_token_details`, `total_cost_details` | New: per-category dicts, unlike `threads.list_traces` these are not wrapped in `.raw` | | *(not available)* | `feedback_stats` | New | | Before (legacy `ListThreadsItem`) | After (new `Thread`) | Notes | | - | - | - | | `thread_id` | `thread_id` | Unchanged | | `runs` (full embedded `Run[]`) | *(not available)* | Use `threads.listTraces` for per-trace detail | | `count` | `count` | Unchanged | | `min_start_time` | `min_start_time` | Unchanged | | `max_start_time` | `max_start_time` | Unchanged | | `total_tokens` | `total_tokens` | Unchanged | | `total_cost` | `total_cost` | Unchanged | | `latency_p50`, `latency_p99` | `latency_p50`, `latency_p99` | Unchanged | | `feedback_stats` | `feedback_stats` | Unchanged | | `first_inputs`, `last_outputs` | `first_inputs`, `last_outputs` | Unchanged | | `last_error` | `last_error` | Unchanged | | *(not available)* | `start_time` | New: a reference start time for this row, for example for sorting | | *(not available)* | `trace_id` | New: a representative root trace UUID, for example for deep links | | *(not available)* | `first_trace_id`, `last_trace_id` | New: chronologically first/last trace UUID in the query window | | *(not available)* | `num_errored_turns` | New | | *(not available)* | `total_token_details`, `total_cost_details` | New: per-category dicts, unlike `threads.listTraces` these are not wrapped in `.raw` | `Thread` has 19 fields: `threadId`, `count`, `feedbackStats`, `firstInputs`, `firstTraceId`, `lastError`, `lastOutputs`, `lastTraceId`, `latencyP50`, `latencyP99`, `maxStartTime`, `minStartTime`, `numErroredTurns`, `startTime`, `totalCost`, `totalCostDetails`, `totalTokenDetails`, `totalTokens`, `traceId` (all `Optional`). The legacy SDK never had a typed response for this. Java's closest equivalent grouped raw `runs().query()` results by the `thread_id` metadata client-side. Every field below is new. | New `Thread` method | Notes | | - | - | | `threadId()` | | | `count()` | | | `minStartTime()`, `maxStartTime()`, `startTime()` | | | `firstTraceId()`, `lastTraceId()`, `traceId()` | `traceId()` is a representative root trace UUID, for example for deep links, in addition to the first/last trace UUIDs | | `firstInputs()`, `lastOutputs()` | Truncated previews from the first/last trace | | `lastError()` | | | `numErroredTurns()` | | | `latencyP50()`, `latencyP99()` | | | `totalTokens()`, `totalCost()` | | | `totalTokenDetails()`, `totalCostDetails()` | Per-category maps | | `feedbackStats()` | | `Thread` has 19 fields, in `PascalCase` Go struct form (e.g. `ThreadID`, `Count`, `LatencyP50`). The legacy SDK never had a typed response for this. Go's closest equivalent grouped raw `Runs.Query()` results by the `thread_id` metadata client-side. Every field below is new. | New `Thread` field | Notes | | - | - | | `ThreadID` | | | `Count` | | | `MinStartTime`, `MaxStartTime`, `StartTime` | | | `FirstTraceID`, `LastTraceID`, `TraceID` | `TraceID` is a representative root trace UUID, for example for deep links, in addition to the first/last trace UUIDs | | `FirstInputs`, `LastOutputs` | Truncated previews from the first/last trace | | `LastError` | | | `NumErroredTurns` | | | `LatencyP50`, `LatencyP99` | | | `TotalTokens`, `TotalCost` | | | `TotalTokenDetails`, `TotalCostDetails` | Per-category maps | | `FeedbackStats` | | JSON response fields use `snake_case`: `thread_id`, `count`, `feedback_stats`, `first_inputs`, `first_trace_id`, `last_error`, `last_outputs`, `last_trace_id`, `latency_p50`, `latency_p99`, `max_start_time`, `min_start_time`, `num_errored_turns`, `start_time`, `total_cost`, `total_cost_details`, `total_token_details`, `total_tokens`, `trace_id`. The legacy API never had a dedicated threads endpoint. The closest equivalent was `POST /api/v1/runs/query`, grouped client-side by the `thread_id` metadata. Every field below is new. | New `threads.query` response field | Notes | | - | - | | `thread_id` | | | `count` | | | `min_start_time`, `max_start_time`, `start_time` | | | `first_trace_id`, `last_trace_id`, `trace_id` | `trace_id` is a representative root trace UUID, for example for deep links, in addition to the first/last trace UUIDs | | `first_inputs`, `last_outputs` | Truncated previews from the first/last trace | | `last_error` | | | `num_errored_turns` | | | `latency_p50`, `latency_p99` | | | `total_tokens`, `total_cost` | | | `total_token_details`, `total_cost_details` | Per-category dicts | | `feedback_stats` | | ### Examples #### List threads in a project Fetch every thread with activity in a project during a time range. ```python Before theme={null} from langsmith import Client client = Client() threads = client.list_threads(project_name="default") for thread in threads: print(thread["thread_id"], thread["count"]) ``` ```python After theme={null} import asyncio from datetime import datetime, timedelta, timezone from langsmith import Client async def main(): client = Client() project = await client.aread_project(project_name="default") async for thread in client.threads.query( project_id=str(project.id), min_start_time=datetime.now(timezone.utc) - timedelta(days=30), max_start_time=datetime.now(timezone.utc), ): print(thread.thread_id, thread.count) asyncio.run(main()) ``` ```ts Before theme={null} import { Client } from "langsmith"; const client = new Client(); const threads = await client.listThreads({ projectName: "default" }); for (const thread of threads) { console.log(thread.thread_id, thread.count); } ``` ```ts After theme={null} import { Client } from "langsmith"; const client = new Client(); const project = await client.readProject({ projectName: "default" }); for await (const thread of client.threads.query({ project_id: project.id, min_start_time: new Date(Date.now() - 30 * 24 * 60 * 60 * 1000).toISOString(), max_start_time: new Date().toISOString(), })) { console.log(thread.thread_id, thread.count); } ``` ```kotlin Before theme={null} import com.langchain.smith.client.LangsmithClient import com.langchain.smith.client.okhttp.LangsmithOkHttpClient import com.langchain.smith.models.runs.RunQueryParams import com.langchain.smith.models.sessions.SessionListParams val client: LangsmithClient = LangsmithOkHttpClient.fromEnv() val project = client.sessions().list( SessionListParams.builder().name("default").limit(1L).build() ).items().first() // v1 has no dedicated thread grouping — the generic run query returns raw // root runs, with no built-in way to bucket them by thread. val rootRuns = client.runs().query( RunQueryParams.builder() .addSession(project.id()) .isRoot(true) .build() ).runs() for (run in rootRuns) { println("${run.traceId()} ${run.id()}") } ``` ```kotlin After theme={null} import java.time.OffsetDateTime import com.langchain.smith.client.LangsmithClient import com.langchain.smith.client.okhttp.LangsmithOkHttpClient import com.langchain.smith.models.sessions.SessionListParams import com.langchain.smith.models.threads.ThreadQueryParams val client: LangsmithClient = LangsmithOkHttpClient.fromEnv() val project = client.sessions().list( SessionListParams.builder().name("default").limit(1L).build() ).items().first() val threads = client.threads().query( ThreadQueryParams.builder() .projectId(project.id()) .minStartTime(OffsetDateTime.now().minusMonths(1)) .maxStartTime(OffsetDateTime.now()) .build() ).items() for (thread in threads) { println("${thread.threadId().get()} ${thread.count().get()}") } ``` ```go Before theme={null} package main import ( "context" "fmt" "github.com/langchain-ai/langsmith-go" ) func main() { ctx := context.Background() client := langsmith.NewClient() sessions, err := client.Sessions.List(ctx, langsmith.SessionListParams{ Name: langsmith.F("default"), Limit: langsmith.F(int64(1)), }) if err != nil { panic(err.Error()) } projectID := sessions.Items[0].ID runs, err := client.Runs.Query(ctx, langsmith.RunQueryParams{ Session: langsmith.F([]string{projectID}), IsRoot: langsmith.F(true), }) if err != nil { panic(err.Error()) } threads := map[string]int{} for _, run := range runs.Runs { metadata, ok := run.Extra["metadata"].(map[string]interface{}) if !ok { continue } threadID, ok := metadata["thread_id"].(string) if ok { threads[threadID]++ } } for threadID, count := range threads { fmt.Println(threadID, count) } } ``` ```go After theme={null} package main import ( "context" "fmt" "time" "github.com/langchain-ai/langsmith-go" ) func main() { ctx := context.Background() client := langsmith.NewClient() sessions, err := client.Sessions.List(ctx, langsmith.SessionListParams{ Name: langsmith.F("default"), Limit: langsmith.F(int64(1)), }) if err != nil { panic(err.Error()) } projectID := sessions.Items[0].ID maxStart := time.Now().UTC() minStart := maxStart.AddDate(0, -1, 0) iter := client.Threads.QueryAutoPaging(ctx, langsmith.ThreadQueryParams{ ProjectID: langsmith.F(projectID), MinStartTime: langsmith.F(minStart), MaxStartTime: langsmith.F(maxStart), }) for iter.Next() { thread := iter.Current() fmt.Println(thread.ThreadID, thread.Count) } if err := iter.Err(); err != nil { panic(err.Error()) } } ``` ```bash theme={null} PROJECT_ID=$(curl -s "https://api.smith.langchain.com/api/v1/sessions?name=default&limit=1" \ -H "x-api-key: $LANGSMITH_API_KEY" | jq -r '.[0].id') curl -s -X POST "https://api.smith.langchain.com/api/v1/runs/query" \ -H "x-api-key: $LANGSMITH_API_KEY" \ -H "Content-Type: application/json" \ -d "$(jq -n --arg pid "$PROJECT_ID" '{"session": [$pid], "is_root": true}')" \ | jq '[(.runs // [])[] | select(.extra.metadata.thread_id != null)] | group_by(.extra.metadata.thread_id) | map({ thread_id: .[0].extra.metadata.thread_id, count: length })' ``` ```bash theme={null} PROJECT_ID=$(curl -s "https://api.smith.langchain.com/api/v1/sessions?name=default&limit=1" \ -H "x-api-key: $LANGSMITH_API_KEY" | jq -r '.[0].id') MAX_START=$(date -u +%Y-%m-%dT%H:%M:%SZ) MIN_START=$(date -u -d '-1 month' +%Y-%m-%dT%H:%M:%SZ 2>/dev/null || date -u -v-1m +%Y-%m-%dT%H:%M:%SZ) curl -X POST "https://api.smith.langchain.com/api/v2/threads/query" \ -H "x-api-key: $LANGSMITH_API_KEY" \ -H "Content-Type: application/json" \ -d "$(jq -n --arg pid "$PROJECT_ID" --arg min "$MIN_START" --arg max "$MAX_START" '{ "project_id": $pid, "min_start_time": $min, "max_start_time": $max }')" ``` #### Find threads with errors Find threads that had a turn end in an error. ```python Before theme={null} from langsmith import Client client = Client() threads = client.list_threads(project_name="default", filter='eq(status, "error")') for thread in threads: print(thread["thread_id"]) ``` ```python After theme={null} import asyncio from datetime import datetime, timedelta, timezone from langsmith import Client async def main(): client = Client() project = await client.aread_project(project_name="default") async for thread in client.threads.query( project_id=str(project.id), min_start_time=datetime.now(timezone.utc) - timedelta(days=30), max_start_time=datetime.now(timezone.utc), filter='eq(status, "error")', ): print(thread.thread_id, thread.last_error) asyncio.run(main()) ``` ```ts Before theme={null} import { Client } from "langsmith"; const client = new Client(); const threads = await client.listThreads({ projectName: "default", filter: 'eq(status, "error")', }); for (const thread of threads) { console.log(thread.thread_id, thread.last_error); } ``` ```ts After theme={null} import { Client } from "langsmith"; const client = new Client(); const project = await client.readProject({ projectName: "default" }); for await (const thread of client.threads.query({ project_id: project.id, min_start_time: new Date(Date.now() - 30 * 24 * 60 * 60 * 1000).toISOString(), max_start_time: new Date().toISOString(), filter: 'eq(status, "error")', })) { console.log(thread.thread_id, thread.last_error); } ``` ```kotlin Before theme={null} import com.langchain.smith.client.LangsmithClient import com.langchain.smith.client.okhttp.LangsmithOkHttpClient import com.langchain.smith.models.runs.RunQueryParams import com.langchain.smith.models.sessions.SessionListParams import kotlin.jvm.optionals.getOrNull val client: LangsmithClient = LangsmithOkHttpClient.fromEnv() val project = client.sessions().list( SessionListParams.builder().name("default").limit(1L).build() ).items().first() val rootRuns = client.runs().query( RunQueryParams.builder() .addSession(project.id()) .isRoot(true) .filter("eq(status, \"error\")") .build() ).runs() for (run in rootRuns) { println("${run.traceId()} ${run.error().getOrNull()}") } ``` ```kotlin After theme={null} import java.time.OffsetDateTime import com.langchain.smith.client.LangsmithClient import com.langchain.smith.client.okhttp.LangsmithOkHttpClient import com.langchain.smith.models.sessions.SessionListParams import com.langchain.smith.models.threads.ThreadQueryParams import kotlin.jvm.optionals.getOrNull val client: LangsmithClient = LangsmithOkHttpClient.fromEnv() val project = client.sessions().list( SessionListParams.builder().name("default").limit(1L).build() ).items().first() val threads = client.threads().query( ThreadQueryParams.builder() .projectId(project.id()) .minStartTime(OffsetDateTime.now().minusMonths(1)) .maxStartTime(OffsetDateTime.now()) .filter("eq(status, \"error\")") .build() ).items() for (thread in threads) { println("${thread.threadId().get()} ${thread.lastError().getOrNull()}") } ``` ```go Before theme={null} package main import ( "context" "fmt" "github.com/langchain-ai/langsmith-go" ) func main() { ctx := context.Background() client := langsmith.NewClient() sessions, err := client.Sessions.List(ctx, langsmith.SessionListParams{ Name: langsmith.F("default"), Limit: langsmith.F(int64(1)), }) if err != nil { panic(err.Error()) } projectID := sessions.Items[0].ID runs, err := client.Runs.Query(ctx, langsmith.RunQueryParams{ Session: langsmith.F([]string{projectID}), IsRoot: langsmith.F(true), Filter: langsmith.F(`eq(status, "error")`), }) if err != nil { panic(err.Error()) } threadIDs := map[string]bool{} for _, run := range runs.Runs { metadata, ok := run.Extra["metadata"].(map[string]interface{}) if !ok { continue } if threadID, ok := metadata["thread_id"].(string); ok { threadIDs[threadID] = true } } for threadID := range threadIDs { fmt.Println(threadID) } } ``` ```go After theme={null} package main import ( "context" "fmt" "time" "github.com/langchain-ai/langsmith-go" ) func main() { ctx := context.Background() client := langsmith.NewClient() sessions, err := client.Sessions.List(ctx, langsmith.SessionListParams{ Name: langsmith.F("default"), Limit: langsmith.F(int64(1)), }) if err != nil { panic(err.Error()) } projectID := sessions.Items[0].ID maxStart := time.Now().UTC() minStart := maxStart.AddDate(0, -1, 0) iter := client.Threads.QueryAutoPaging(ctx, langsmith.ThreadQueryParams{ ProjectID: langsmith.F(projectID), MinStartTime: langsmith.F(minStart), MaxStartTime: langsmith.F(maxStart), Filter: langsmith.F(`eq(status, "error")`), }) for iter.Next() { thread := iter.Current() fmt.Println(thread.ThreadID, thread.LastError) } if err := iter.Err(); err != nil { panic(err.Error()) } } ``` ```bash theme={null} PROJECT_ID=$(curl -s "https://api.smith.langchain.com/api/v1/sessions?name=default&limit=1" \ -H "x-api-key: $LANGSMITH_API_KEY" | jq -r '.[0].id') curl -s -X POST "https://api.smith.langchain.com/api/v1/runs/query" \ -H "x-api-key: $LANGSMITH_API_KEY" \ -H "Content-Type: application/json" \ -d "$(jq -n --arg pid "$PROJECT_ID" '{"session": [$pid], "is_root": true, "filter": "eq(status, \"error\")"}')" \ | jq -r '[(.runs // [])[].extra.metadata.thread_id] | unique | .[]' ``` ```bash theme={null} PROJECT_ID=$(curl -s "https://api.smith.langchain.com/api/v1/sessions?name=default&limit=1" \ -H "x-api-key: $LANGSMITH_API_KEY" | jq -r '.[0].id') MAX_START=$(date -u +%Y-%m-%dT%H:%M:%SZ) MIN_START=$(date -u -d '-1 month' +%Y-%m-%dT%H:%M:%SZ 2>/dev/null || date -u -v-1m +%Y-%m-%dT%H:%M:%SZ) curl -X POST "https://api.smith.langchain.com/api/v2/threads/query" \ -H "x-api-key: $LANGSMITH_API_KEY" \ -H "Content-Type: application/json" \ -d "$(jq -n --arg pid "$PROJECT_ID" --arg min "$MIN_START" --arg max "$MAX_START" '{ "project_id": $pid, "min_start_time": $min, "max_start_time": $max, "filter": "eq(status, \"error\")" }')" ``` ## Threads: list traces Retrieve all traces belonging to a specific thread within a project. ### Main changes #### Method name | Before | After | | - | - | | `client.read_thread()` | `client.threads.list_traces()` | `client.threads.list_traces()` is now async. Call it with `await`. See the [reference](https://reference.langchain.com/python/langsmith/_openapi_client/resources/threads/ThreadsResource/list_traces) for the full parameter and field list. | Before | After | | - | - | | `client.readThread()` | `client.threads.listTraces()` | See the [reference](https://reference.langchain.com/javascript/langsmith/_openapi_client/Langsmith/Threads/listTraces) for the full parameter and field list. Java never had a dedicated per-thread method. The closest legacy equivalent is the generic run query filtered by the `thread_id` metadata convention. | Before | After | | - | - | | `client.runs().query()` (filtered by `thread_id`) | `client.threads().listTraces()` | See the [reference](https://javadoc.io/doc/com.langchain.smith/langsmith-java/latest/com/langchain/smith/services/blocking/ThreadService.html) for the full parameter list. Go never had a dedicated per-thread method. The closest legacy equivalent is the generic run query filtered by the `thread_id` metadata convention. | Before | After | | - | - | | `client.Runs.Query()` (filtered by `thread_id`) | `client.Threads.ListTraces()` | See the [reference](https://pkg.go.dev/github.com/langchain-ai/langsmith-go#ThreadService.ListTracesAutoPaging) for the full parameter list. | Before | After | | - | - | | `POST /api/v1/runs/query` (`filter=eq(thread_id, ...)`) | `GET /api/v2/threads/{thread_id}/traces` | See the [API doc](/langsmith/smith-api/threads/query-thread-traces) for the full parameter and field list. #### Query parameters `read_thread`'s `is_root` has no new equivalent. `list_traces` always returns traces (root runs) only, matching its name. `read_thread`'s `order` (asc/desc) also has no new equivalent: results are always sorted by `start_time` ascending, a fixed server-side order. | Before (`read_thread`) | After (`list_traces`) | Notes | | - | - | - | | `thread_id` | `thread_id` (path param) | Unchanged | | `project_id` XOR `project_name` | `project_id` | The new method takes only the UUID | | `is_root` | *(not available)* | The new method always returns traces (root runs) only | | `order` | *(not available)* | No sort/order field on the new method | | `filter` | `filter` | Same syntax, now evaluated against each root trace run | | `select` (arbitrary run field list) | `selects` | The new method uses `ThreadTraceSelectField`, a 24-value uppercase enum | | *(not available)* | `page_size` + `cursor` | The new method adds cursor pagination | `readThread`'s `isRoot` has no new equivalent. `listTraces` always returns traces (root runs) only, matching its name. `readThread`'s `order` (asc/desc) also has no new equivalent: results are always sorted by `start_time` ascending, a fixed server-side order. | Before (`readThread`) | After (`listTraces`) | Notes | | - | - | - | | `threadId` | `threadId` (path param) | Unchanged | | `projectId` XOR `projectName` | `project_id` | The new method takes only the UUID | | `isRoot` | *(not available)* | The new method always returns traces (root runs) only | | `order` | *(not available)* | No sort/order field on the new method | | `filter` | `filter` | Same syntax, now evaluated against each root trace run | | `select` (arbitrary run field list) | `selects` | The new method uses a 24-value uppercase enum | | *(not available)* | `page_size` + `cursor` | The new method adds cursor pagination | No query parameters to map. There was no dedicated method. `listTraces(threadId, params)` takes `projectId`, `filter`, `pageSize`, `cursor`, `selects` (24-value enum). Results are always sorted by `startTime` ascending, a fixed server-side order. No query parameters to map. There was no dedicated method. `ListTraces(ctx, threadID, params)` takes `ProjectID`, `Filter`, `PageSize`, `Cursor`, `Selects` (24-value enum). Results are always sorted by `StartTime` ascending, a fixed server-side order. `GET /api/v2/threads/{thread_id}/traces` query params: `project_id`, `filter`, `page_size`, `cursor`, `selects` (repeatable), all `snake_case`. Results are always sorted by `start_time` ascending, a fixed server-side order. #### Response fields The legacy `read_thread` returns full `Run` objects (a generator). The new `ThreadTrace` is lightweight: preview fields (`inputs_preview`/`outputs_preview`) instead of full `inputs`/`outputs`, no embedded child runs. `selects` controls what's populated, the same as `traces.query`. | Before (legacy `Run` field, via `read_thread`) | After (new `ThreadTrace` field) | Notes | | - | - | - | | `id` | *(not available)* | the legacy root run `id` and `trace_id` were identical; the new API exposes only `trace_id` | | `trace_id` | `trace_id` | Returned by default when `selects` is omitted | | `name` | `name` | Omitted unless included in `selects` | | `start_time` | `start_time` | Omitted unless included in `selects` | | `end_time` | `end_time` | Omitted unless included in `selects` | | `run_type` | `op` | Renamed; encoded as a number instead of a string | | `inputs` | `inputs_preview`, or `inputs` for the untruncated payload | Truncated preview by default; select `INPUTS` for the full payload | | `outputs` | `outputs_preview`, or `outputs` for the untruncated payload | Truncated preview by default; select `OUTPUTS` for the full payload | | `error` | `error_preview`, or `error` for the full message | Truncated summary by default; select `ERROR` for the full error message | | `latency` (property) | `latency` | Native field instead of a computed `timedelta` property | | `total_tokens`, `prompt_tokens`, `completion_tokens` | `total_tokens`, `prompt_tokens`, `completion_tokens` | Unchanged | | `total_cost`, `prompt_cost`, `completion_cost` | `total_cost`, `prompt_cost`, `completion_cost` | Unchanged | | `prompt_token_details`, `completion_token_details` | `prompt_token_details`, `completion_token_details` | Field now wraps the dict; access `.raw` | | `prompt_cost_details`, `completion_cost_details` | `prompt_cost_details`, `completion_cost_details` | Field now wraps the dict; access `.raw` | | `first_token_time` | `first_token_time` | Omitted unless included in `selects` | | *(not available)* | `thread_id` | New: the thread UUID this trace belongs to | | `child_runs`, `child_run_ids` | *(not available)* | No embedded child runs; use `traces.list_runs` for descendant runs | The legacy `readThread` returns full `Run` objects (an async generator). The new `ThreadTrace` is lightweight: preview fields (`inputs_preview`/`outputs_preview`) instead of full `inputs`/`outputs`, no embedded child runs. `selects` controls what is populated, the same as `traces.query`. | Before (legacy `Run` field, via `readThread`) | After (new `ThreadTrace` field) | Notes | | - | - | - | | `id` | *(not available)* | the legacy root run `id` and `trace_id` were identical; the new API exposes only `trace_id` | | `trace_id` | `trace_id` | Returned by default when `selects` is omitted | | `name` | `name` | Omitted unless included in `selects` | | `start_time` | `start_time` | Omitted unless included in `selects` | | `end_time` | `end_time` | Omitted unless included in `selects` | | `run_type` | `op` | Renamed; encoded as a number instead of a string | | `inputs` | `inputs_preview`, or `inputs` for the untruncated payload | Truncated preview by default; select `INPUTS` for the full payload | | `outputs` | `outputs_preview`, or `outputs` for the untruncated payload | Truncated preview by default; select `OUTPUTS` for the full payload | | `error` | `error_preview`, or `error` for the full message | Truncated summary by default; select `ERROR` for the full error message | | `latency` | `latency` | Native field on the new type | | `total_tokens`, `prompt_tokens`, `completion_tokens` | `total_tokens`, `prompt_tokens`, `completion_tokens` | Unchanged | | `total_cost`, `prompt_cost`, `completion_cost` | `total_cost`, `prompt_cost`, `completion_cost` | Unchanged | | `prompt_token_details`, `completion_token_details` | `prompt_token_details`, `completion_token_details` | Unchanged | | `prompt_cost_details`, `completion_cost_details` | `prompt_cost_details`, `completion_cost_details` | Unchanged | | `first_token_time` | `first_token_time` | Omitted unless included in `selects` | | *(not available)* | `thread_id` | New: the thread UUID this trace belongs to | | `child_runs`, `child_run_ids` | *(not available)* | No embedded child runs; use `traces.listRuns` for descendant runs | `ThreadTrace` has 24 `Optional` fields: `traceId`, `threadId`, `name`, `startTime`, `endTime`, `latency`, `op`, token/cost fields with per-category `_details`, `inputsPreview`/`outputsPreview`/`inputs`/`outputs`, `errorPreview`/`error`, `firstTokenTime`. | Before (legacy `RunSchema` method) | After (new `ThreadTrace` method) | Notes | | - | - | - | | `id()` | *(not available)* | the legacy root run `id()` and `traceId()` were identical; the new API exposes only `traceId()` | | `traceId()` | `traceId()` | Returned by default when `selects` is omitted | | `name()` | `name()` | Omitted unless included in `selects` | | `startTime()` | `startTime()` | Omitted unless included in `selects` | | `endTime()` | `endTime()` | Omitted unless included in `selects` | | `runType()` | `op()` | Renamed; encoded as a number instead of a string | | `inputs()` | `inputsPreview()`, or `inputs()` for the untruncated payload | Truncated preview by default; select `INPUTS` for the full payload | | `outputs()` | `outputsPreview()`, or `outputs()` for the untruncated payload | Truncated preview by default; select `OUTPUTS` for the full payload | | `error()` | `errorPreview()`, or `error()` for the full message | Truncated summary by default; select `ERROR` for the full error message | | `latency()` | `latency()` | Unchanged | | `totalTokens()`, `promptTokens()`, `completionTokens()` | `totalTokens()`, `promptTokens()`, `completionTokens()` | Unchanged | | `totalCost()`, `promptCost()`, `completionCost()` | `totalCost()`, `promptCost()`, `completionCost()` | Unchanged | | `promptTokenDetails()`, `completionTokenDetails()` | `promptTokenDetails()`, `completionTokenDetails()` | Unchanged | | `promptCostDetails()`, `completionCostDetails()` | `promptCostDetails()`, `completionCostDetails()` | Unchanged | | `firstTokenTime()` | `firstTokenTime()` | Omitted unless included in `selects` | | *(not available)* | `threadId()` | New: the thread UUID this trace belongs to | | `childRuns()`, `childRunIds()` | *(not available)* | No embedded child runs; use `traces().listRuns()` for descendant runs | `ThreadTrace` has 24 fields, in `PascalCase` Go struct form. | Before (legacy root `Run` field) | After (new `ThreadTrace` field) | Notes | | - | - | - | | `ID` | *(not available)* | the legacy root run `ID` and `TraceID` were identical; the new API exposes only `TraceID` | | `TraceID` | `TraceID` | Returned by default when `Selects` is omitted | | `Name` | `Name` | Omitted unless included in `Selects` | | `StartTime` | `StartTime` | Omitted unless included in `Selects` | | `EndTime` | `EndTime` | Omitted unless included in `Selects` | | `RunType` | `Op` | Renamed; encoded as a number instead of a string | | `Inputs` | `InputsPreview`, or `Inputs` for the untruncated payload | Truncated preview by default; select `INPUTS` for the full payload | | `Outputs` | `OutputsPreview`, or `Outputs` for the untruncated payload | Truncated preview by default; select `OUTPUTS` for the full payload | | `Error` | `ErrorPreview`, or `Error` for the full message | Truncated summary by default; select `ERROR` for the full error message | | `Latency` | `Latency` | Unchanged | | `TotalTokens`, `PromptTokens`, `CompletionTokens` | `TotalTokens`, `PromptTokens`, `CompletionTokens` | Unchanged | | `TotalCost`, `PromptCost`, `CompletionCost` | `TotalCost`, `PromptCost`, `CompletionCost` | Unchanged | | `PromptTokenDetails`, `CompletionTokenDetails` | `PromptTokenDetails`, `CompletionTokenDetails` | Unchanged | | `PromptCostDetails`, `CompletionCostDetails` | `PromptCostDetails`, `CompletionCostDetails` | Unchanged | | `FirstTokenTime` | `FirstTokenTime` | Omitted unless included in `Selects` | | *(not available)* | `ThreadID` | New: the thread UUID this trace belongs to | | `ChildRuns`, `ChildRunIDs` | *(not available)* | No embedded child runs; use `Traces.ListRuns` for descendant runs | JSON response fields use `snake_case`, matching the table below. | Before (legacy root run field) | After (new `ThreadTrace` field) | Notes | | - | - | - | | `id` | *(not available)* | the legacy root run `id` and `trace_id` were identical; the new API exposes only `trace_id` | | `trace_id` | `trace_id` | Returned by default when `selects` is omitted | | `name` | `name` | Omitted unless included in `selects` | | `start_time` | `start_time` | Omitted unless included in `selects` | | `end_time` | `end_time` | Omitted unless included in `selects` | | `run_type` | `op` | Renamed; encoded as a number instead of a string | | `inputs` | `inputs_preview`, or `inputs` for the untruncated payload | Truncated preview by default; select `INPUTS` for the full payload | | `outputs` | `outputs_preview`, or `outputs` for the untruncated payload | Truncated preview by default; select `OUTPUTS` for the full payload | | `error` | `error_preview`, or `error` for the full message | Truncated summary by default; select `ERROR` for the full error message | | `latency` | `latency` | Unchanged | | `total_tokens`, `prompt_tokens`, `completion_tokens` | `total_tokens`, `prompt_tokens`, `completion_tokens` | Unchanged | | `total_cost`, `prompt_cost`, `completion_cost` | `total_cost`, `prompt_cost`, `completion_cost` | Unchanged | | `prompt_token_details`, `completion_token_details` | `prompt_token_details`, `completion_token_details` | Unchanged | | `prompt_cost_details`, `completion_cost_details` | `prompt_cost_details`, `completion_cost_details` | Unchanged | | `first_token_time` | `first_token_time` | Omitted unless included in `selects` | | *(not available)* | `thread_id` | New: the thread UUID this trace belongs to | | `child_runs`, `child_run_ids` | *(not available)* | No embedded child runs; use `traces.list_runs` for descendant runs | ### Examples #### List every trace (turn) in a thread Fetch all the traces (conversation turns) that belong to one thread. ```python Before theme={null} from langsmith import Client client = Client() thread_id = "" for run in client.read_thread(thread_id=thread_id, project_name="default"): print(run.id, run.start_time) ``` ```python After theme={null} import asyncio from langsmith import Client async def main(): client = Client() project = await client.aread_project(project_name="default") thread_id = "" async for trace in client.threads.list_traces( thread_id, project_id=str(project.id), selects=["TRACE_ID", "START_TIME"] ): print(trace.trace_id, trace.start_time) asyncio.run(main()) ``` ```ts Before theme={null} import { Client } from "langsmith"; const client = new Client(); let threadId = ""; for await (const run of client.readThread({ threadId, projectName: "default" })) { console.log(run.id, run.start_time); } ``` ```ts After theme={null} import { Client } from "langsmith"; const client = new Client(); const project = await client.readProject({ projectName: "default" }); let threadId = ""; for await (const trace of client.threads.listTraces(threadId, { project_id: project.id, selects: ["TRACE_ID", "START_TIME"], })) { console.log(trace.trace_id, trace.start_time); } ``` ```kotlin Before theme={null} import com.langchain.smith.client.LangsmithClient import com.langchain.smith.client.okhttp.LangsmithOkHttpClient import com.langchain.smith.models.runs.RunQueryParams import com.langchain.smith.models.sessions.SessionListParams val client: LangsmithClient = LangsmithOkHttpClient.fromEnv() val project = client.sessions().list( SessionListParams.builder().name("default").limit(1L).build() ).items().first() var threadId = "" val runs = client.runs().query( RunQueryParams.builder() .addSession(project.id()) .isRoot(true) .filter("eq(thread_id, \"$threadId\")") .build() ).runs() for (run in runs) { println("${run.id()} ${run.startTime().get()}") } ``` ```kotlin After theme={null} import com.langchain.smith.client.LangsmithClient import com.langchain.smith.client.okhttp.LangsmithOkHttpClient import com.langchain.smith.models.sessions.SessionListParams import com.langchain.smith.models.threads.ThreadListTracesParams val client: LangsmithClient = LangsmithOkHttpClient.fromEnv() val project = client.sessions().list( SessionListParams.builder().name("default").limit(1L).build() ).items().first() var threadId = "" val traces = client.threads().listTraces( threadId, ThreadListTracesParams.builder() .projectId(project.id()) .addSelect(ThreadListTracesParams.Select.TRACE_ID) .addSelect(ThreadListTracesParams.Select.START_TIME) .build() ).items() for (trace in traces) { println("${trace.traceId().get()} ${trace.startTime().get()}") } ``` ```go Before theme={null} package main import ( "context" "fmt" "time" "github.com/langchain-ai/langsmith-go" ) func main() { ctx := context.Background() client := langsmith.NewClient() sessions, err := client.Sessions.List(ctx, langsmith.SessionListParams{ Name: langsmith.F("default"), Limit: langsmith.F(int64(1)), }) if err != nil { panic(err.Error()) } projectID := sessions.Items[0].ID threadID := "" runs, err := client.Runs.Query(ctx, langsmith.RunQueryParams{ Session: langsmith.F([]string{projectID}), IsRoot: langsmith.F(true), Filter: langsmith.F(fmt.Sprintf(`eq(thread_id, "%s")`, threadID)), }) if err != nil { panic(err.Error()) } for _, run := range runs.Runs { fmt.Println(run.ID, run.StartTime) } } ``` ```go After theme={null} package main import ( "context" "fmt" "time" "github.com/langchain-ai/langsmith-go" ) func main() { ctx := context.Background() client := langsmith.NewClient() sessions, err := client.Sessions.List(ctx, langsmith.SessionListParams{ Name: langsmith.F("default"), Limit: langsmith.F(int64(1)), }) if err != nil { panic(err.Error()) } projectID := sessions.Items[0].ID threadID := "" iter := client.Threads.ListTracesAutoPaging(ctx, threadID, langsmith.ThreadListTracesParams{ ProjectID: langsmith.F(projectID), Selects: langsmith.F([]langsmith.ThreadListTracesParamsSelect{langsmith.ThreadListTracesParamsSelectTraceID, langsmith.ThreadListTracesParamsSelectStartTime}), }) for iter.Next() { trace := iter.Current() fmt.Println(trace.TraceID, trace.StartTime) } if err := iter.Err(); err != nil { panic(err.Error()) } } ``` ```bash theme={null} PROJECT_ID=$(curl -s "https://api.smith.langchain.com/api/v1/sessions?name=default&limit=1" \ -H "x-api-key: $LANGSMITH_API_KEY" | jq -r '.[0].id') THREAD_ID="" curl -s -X POST "https://api.smith.langchain.com/api/v1/runs/query" \ -H "x-api-key: $LANGSMITH_API_KEY" \ -H "Content-Type: application/json" \ -d "$(jq -n --arg pid "$PROJECT_ID" --arg tid "$THREAD_ID" '{"session": [$pid], "is_root": true, "filter": ("eq(thread_id, \"" + $tid + "\")")}')" \ | jq '.runs // []' ``` ```bash theme={null} PROJECT_ID=$(curl -s "https://api.smith.langchain.com/api/v1/sessions?name=default&limit=1" \ -H "x-api-key: $LANGSMITH_API_KEY" | jq -r '.[0].id') THREAD_ID="" curl -G "https://api.smith.langchain.com/api/v2/threads/$THREAD_ID/traces" \ -H "x-api-key: $LANGSMITH_API_KEY" \ --data-urlencode "project_id=$PROJECT_ID" \ --data-urlencode "selects=TRACE_ID" \ --data-urlencode "selects=START_TIME" ``` #### Select specific trace's fields Request just the fields you need instead of every field, to reduce response size. ```python Before theme={null} from langsmith import Client client = Client() thread_id = "" for run in client.read_thread( thread_id=thread_id, project_name="default", select=["id", "total_tokens", "total_cost"], ): print(run.id, run.total_tokens, run.total_cost) ``` ```python After theme={null} import asyncio from langsmith import Client async def main(): client = Client() project = await client.aread_project(project_name="default") thread_id = "" async for trace in client.threads.list_traces( thread_id, project_id=str(project.id), selects=["TRACE_ID", "TOTAL_TOKENS", "TOTAL_COST"], ): print(trace.trace_id, trace.total_tokens, trace.total_cost) asyncio.run(main()) ``` ```ts Before theme={null} import { Client } from "langsmith"; const client = new Client(); let threadId = ""; for await (const run of client.readThread({ threadId, projectName: "default", select: ["id", "total_tokens", "total_cost"], })) { console.log(run.id, run.total_tokens, run.total_cost); } ``` ```ts After theme={null} import { Client } from "langsmith"; const client = new Client(); const project = await client.readProject({ projectName: "default" }); let threadId = ""; for await (const trace of client.threads.listTraces(threadId, { project_id: project.id, selects: ["TRACE_ID", "TOTAL_TOKENS", "TOTAL_COST"], })) { console.log(trace.trace_id, trace.total_tokens, trace.total_cost); } ``` The Before example omits `total_cost` here. Selecting it on the legacy `RunSchema` type triggers a known deserialization bug in the current Java binding (it expects a string, the API returns a number). ```kotlin Before theme={null} import com.langchain.smith.client.LangsmithClient import com.langchain.smith.client.okhttp.LangsmithOkHttpClient import com.langchain.smith.models.runs.RunQueryParams import com.langchain.smith.models.sessions.SessionListParams import kotlin.jvm.optionals.getOrNull val client: LangsmithClient = LangsmithOkHttpClient.fromEnv() val project = client.sessions().list( SessionListParams.builder().name("default").limit(1L).build() ).items().first() var threadId = "" // Note: selecting total_cost here triggers a known deserialization bug in the // v1 Java binding (RunSchema.totalCost() expects a string, the API returns a // number) — omitted to keep this example runnable; see the migration notes. val runs = client.runs().query( RunQueryParams.builder() .addSession(project.id()) .isRoot(true) .filter("eq(thread_id, \"$threadId\")") .addSelect(RunQueryParams.Select.ID) .addSelect(RunQueryParams.Select.TOTAL_TOKENS) .build() ).runs() for (run in runs) { println("${run.id()} ${run.totalTokens().getOrNull()}") } ``` ```kotlin After theme={null} import com.langchain.smith.client.LangsmithClient import com.langchain.smith.client.okhttp.LangsmithOkHttpClient import com.langchain.smith.models.sessions.SessionListParams import com.langchain.smith.models.threads.ThreadListTracesParams import kotlin.jvm.optionals.getOrNull val client: LangsmithClient = LangsmithOkHttpClient.fromEnv() val project = client.sessions().list( SessionListParams.builder().name("default").limit(1L).build() ).items().first() var threadId = "" val traces = client.threads().listTraces( threadId, ThreadListTracesParams.builder() .projectId(project.id()) .addSelect(ThreadListTracesParams.Select.TRACE_ID) .addSelect(ThreadListTracesParams.Select.TOTAL_TOKENS) .addSelect(ThreadListTracesParams.Select.TOTAL_COST) .build() ).items() for (trace in traces) { println("${trace.traceId().get()} ${trace.totalTokens().getOrNull()} ${trace.totalCost().getOrNull()}") } ``` ```go Before theme={null} package main import ( "context" "fmt" "time" "github.com/langchain-ai/langsmith-go" ) func main() { ctx := context.Background() client := langsmith.NewClient() sessions, err := client.Sessions.List(ctx, langsmith.SessionListParams{ Name: langsmith.F("default"), Limit: langsmith.F(int64(1)), }) if err != nil { panic(err.Error()) } projectID := sessions.Items[0].ID threadID := "" runs, err := client.Runs.Query(ctx, langsmith.RunQueryParams{ Session: langsmith.F([]string{projectID}), IsRoot: langsmith.F(true), Filter: langsmith.F(fmt.Sprintf(`eq(thread_id, "%s")`, threadID)), Select: langsmith.F([]langsmith.RunQueryParamsSelect{ langsmith.RunQueryParamsSelectID, langsmith.RunQueryParamsSelectTotalTokens, langsmith.RunQueryParamsSelectTotalCost, }), }) if err != nil { panic(err.Error()) } for _, run := range runs.Runs { fmt.Println(run.ID, run.TotalTokens, run.TotalCost) } } ``` ```go After theme={null} package main import ( "context" "fmt" "time" "github.com/langchain-ai/langsmith-go" ) func main() { ctx := context.Background() client := langsmith.NewClient() sessions, err := client.Sessions.List(ctx, langsmith.SessionListParams{ Name: langsmith.F("default"), Limit: langsmith.F(int64(1)), }) if err != nil { panic(err.Error()) } projectID := sessions.Items[0].ID threadID := "" iter := client.Threads.ListTracesAutoPaging(ctx, threadID, langsmith.ThreadListTracesParams{ ProjectID: langsmith.F(projectID), Selects: langsmith.F([]langsmith.ThreadListTracesParamsSelect{ langsmith.ThreadListTracesParamsSelectTraceID, langsmith.ThreadListTracesParamsSelectTotalTokens, langsmith.ThreadListTracesParamsSelectTotalCost, }), }) for iter.Next() { trace := iter.Current() fmt.Println(trace.TraceID, trace.TotalTokens, trace.TotalCost) } if err := iter.Err(); err != nil { panic(err.Error()) } } ``` ```bash theme={null} PROJECT_ID=$(curl -s "https://api.smith.langchain.com/api/v1/sessions?name=default&limit=1" \ -H "x-api-key: $LANGSMITH_API_KEY" | jq -r '.[0].id') THREAD_ID="" curl -s -X POST "https://api.smith.langchain.com/api/v1/runs/query" \ -H "x-api-key: $LANGSMITH_API_KEY" \ -H "Content-Type: application/json" \ -d "$(jq -n --arg pid "$PROJECT_ID" --arg tid "$THREAD_ID" '{"session": [$pid], "is_root": true, "filter": ("eq(thread_id, \"" + $tid + "\")"), "select": ["id", "total_tokens", "total_cost"]}')" \ | jq '.runs // []' ``` ```bash theme={null} PROJECT_ID=$(curl -s "https://api.smith.langchain.com/api/v1/sessions?name=default&limit=1" \ -H "x-api-key: $LANGSMITH_API_KEY" | jq -r '.[0].id') THREAD_ID="" curl -G "https://api.smith.langchain.com/api/v2/threads/$THREAD_ID/traces" \ -H "x-api-key: $LANGSMITH_API_KEY" \ --data-urlencode "project_id=$PROJECT_ID" \ --data-urlencode "selects=TRACE_ID" \ --data-urlencode "selects=TOTAL_TOKENS" \ --data-urlencode "selects=TOTAL_COST" ``` ## See also * [Traces](/langsmith/smithdb-sdk-migration-traces) * [Dataset experiment runs](/langsmith/smithdb-sdk-migration-experiments) * [Migration overview](/langsmith/smithdb-sdk-migration) ***
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