LangSmith MCP Server

Tools · 15

• get_thread_history Retrieve message history for a conversation thread. Uses char-based pagination: pass page_number (1-based), and use returned total_pages to request more pages. Optional max_chars_per_page and preview_chars control page size and long-string truncation.
• list_prompts Fetch prompts from LangSmith with optional filtering by visibility (public/private) and limit.
• get_prompt_by_name Get a specific prompt by its exact name, returning the prompt details and template.
• push_prompt Documentation-only: how to create and push prompts to LangSmith.
• fetch_runs Fetch LangSmith runs (traces, tools, chains, etc.) from one or more projects. Supports filters (run_type, error, is_root), FQL (filter, trace_filter, tree_filter), and ordering. When trace_id is set, returns char-based paginated pages; otherwise returns one batch up to limit. Always pass limit and page_number.
• list_projects List LangSmith projects with optional filtering by name, dataset, and detail level (simplified vs full).
• list_datasets Fetch datasets with filtering by ID, type, name, name substring, or metadata.
• list_examples Fetch examples from a dataset by dataset ID/name or example IDs, with filter, metadata, splits, and optional as_of version.
• read_dataset Read a single dataset by ID or name.
• read_example Read a single example by ID, with optional as_of version.
• create_dataset Documentation-only: how to create datasets in LangSmith.
• update_examples Documentation-only: how to update dataset examples in LangSmith.
• list_experiments List experiment projects (reference projects) for a dataset. Requires reference_dataset_id or reference_dataset_name. Returns key metrics (latency, cost, feedback stats).
• run_experiment Documentation-only: how to run experiments and evaluations in LangSmith.
• get_billing_usage Fetch organization billing usage (e.g. trace counts) for a date range. Optional workspace filter; returns metrics with workspace names inline.