Common

Shared utilities used across every ra-mcp package (ra-mcp-common, module ra_mcp_common). No internal dependencies.

HTTP Client

Source: packages/libs/common/src/ra_mcp_common/http_client.py

HTTPClient is the centralized async httpx client used by every domain library. It adds exponential-backoff retry on transient failures (429, 500, 502, 503, 504, timeouts, connection errors), structured logging, and OpenTelemetry spans/metrics.

Member	Description
`HTTPClient(...)`	Construct a client with per-timeout, retry, and connection-pool settings.
`get_json(url, params=None, timeout=30, headers=None)`	GET and parse a JSON response.
`get_xml(url, params=None, timeout=30, headers=None)`	GET raw XML bytes.
`get_content(url, timeout=30, headers=None)`	GET raw bytes; returns `None` on 404/non-200.
`aclose()`	Close the underlying `httpx.AsyncClient`.
`default_http_client` / `get_http_client(enable_logging=False)`	Shared singleton accessor.

Formatting Utilities

Source: packages/libs/common/src/ra_mcp_common/formatting.py

Presentation helpers shared by the CLI and MCP formatters (text truncation, snippet highlighting, reference-code formatting).

Datasets

Source: packages/libs/common/src/ra_mcp_common/datasets.py

Resolves LanceDB dataset paths for the optional dataset modules, with a local → mount → Hugging Face Hub fallback chain.

Telemetry

Source: packages/libs/common/src/ra_mcp_common/telemetry.py

Thin wrappers over opentelemetry-api that return no-op instances when no SDK is configured (zero overhead when telemetry is disabled).

Member	Description
`get_tracer(name)`	Get a tracer for a component (e.g. `ra_mcp.http_client`).
`get_meter(name)`	Get a meter for a component.
`record_span_exception(logger, exc)`	Record an exception as a structured `exception.*` log record (the OTel-recommended replacement for the deprecated span-event API).

See Observability for the full instrumentation map.