MCP semantic conventions - #2083

…en-telemetry/semantic-conventions#2083

- Change mcp.tool.name to gen_ai.tool.name
- Change mcp.prompt.name to gen_ai.prompt.name
- Change mcp.request.id to jsonrpc.request.id
- Change rpc.jsonrpc.error_code to rpc.response.status_code
- Update network.transport values from 'stdio' to 'pipe' and 'sse'/'http' to 'tcp'
- Add gen_ai.operation.name attribute (value: 'execute_tool' for tools/call)
- Update histogram bucket boundaries to match semantic conventions spec
- Update tests to verify new attribute names

Co-authored-by: stephentoub <2642209+stephentoub@users.noreply.github.com>

Updates FastMCP's telemetry to align with the new MCP semantic conventions
from open-telemetry/semantic-conventions#2083. This gives us interoperability
with other MCP implementations while keeping fastmcp.* attributes for things
unique to our framework.

Changes:
- Span names now follow `{method} {target}` format (e.g., `tools/call greet`)
- Added `mcp.method.name` and `mcp.resource.uri` attributes
- Renamed `fastmcp.session.id` to standard `mcp.session.id`
- Kept fastmcp.* attributes for server name, component info, provider details

🤖 Generated with Claude Code

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Align Sentry MCP attributes with the OTel MCP semantic conventions
that merged in open-telemetry/semantic-conventions#2083 (Jan 2026).

OTel's MCP convention is deliberately minimal: only 4 mcp.* registry
attributes, reusing existing gen_ai.*, network.*, jsonrpc.*, and
error.* namespaces for everything else. This commit brings Sentry
conventions in line with that approach.

Changes:

Set is_in_otel=true on 4 direct matches:
- mcp.method.name
- mcp.protocol.version
- mcp.resource.uri
- mcp.session.id

Deprecated 7 attributes with backfill to OTel equivalents:
- mcp.tool.name → gen_ai.tool.name
- mcp.prompt.name → gen_ai.prompt.name
- mcp.tool.result.content → gen_ai.tool.call.result
- mcp.tool.result.is_error → error.type
- mcp.request.id → jsonrpc.request.id
- mcp.transport → network.transport
- mcp.resource.protocol → network.protocol.name

Created 3 new attributes:
- gen_ai.prompt.name (OTel gen_ai registry, aliased from mcp.prompt.name)
- jsonrpc.request.id (OTel MCP common refs, aliased from mcp.request.id)
- jsonrpc.protocol.version (OTel MCP common refs)

27 Sentry-only attributes remain unchanged (mcp.client.*, mcp.server.*,
mcp.logging.*, mcp.progress.*, mcp.prompt.result.*, etc.) — these have
no OTel equivalent.

Align Sentry MCP attributes with the OTel MCP semantic conventions
that merged in open-telemetry/semantic-conventions#2083 (Jan 2026).

OTel's MCP convention is deliberately minimal: only 4 mcp.* registry
attributes, reusing existing gen_ai.*, network.*, jsonrpc.*, and
error.* namespaces for everything else. This commit brings Sentry
conventions in line with that approach.

Changes:

Set is_in_otel=true on 4 direct matches:
- mcp.method.name
- mcp.protocol.version
- mcp.resource.uri
- mcp.session.id

Deprecated 7 attributes with backfill to OTel equivalents:
- mcp.tool.name → gen_ai.tool.name
- mcp.prompt.name → gen_ai.prompt.name
- mcp.tool.result.content → gen_ai.tool.call.result
- mcp.tool.result.is_error → error.type
- mcp.request.id → jsonrpc.request.id
- mcp.transport → network.transport
- mcp.resource.protocol → network.protocol.name

Created 3 new attributes:
- gen_ai.prompt.name (OTel gen_ai registry, aliased from mcp.prompt.name)
- jsonrpc.request.id (OTel MCP common refs, aliased from mcp.request.id)
- jsonrpc.protocol.version (OTel MCP common refs)

27 Sentry-only attributes remain unchanged (mcp.client.*, mcp.server.*,
mcp.logging.*, mcp.progress.*, mcp.prompt.result.*, etc.) — these have
no OTel equivalent.

* feat(mcp): align MCP attributes with OTel semantic conventions

Align Sentry MCP attributes with the OTel MCP semantic conventions
that merged in open-telemetry/semantic-conventions#2083 (Jan 2026).

OTel's MCP convention is deliberately minimal: only 4 mcp.* registry
attributes, reusing existing gen_ai.*, network.*, jsonrpc.*, and
error.* namespaces for everything else. This commit brings Sentry
conventions in line with that approach.

Changes:

Set is_in_otel=true on 4 direct matches:
- mcp.method.name
- mcp.protocol.version
- mcp.resource.uri
- mcp.session.id

Deprecated 7 attributes with backfill to OTel equivalents:
- mcp.tool.name → gen_ai.tool.name
- mcp.prompt.name → gen_ai.prompt.name
- mcp.tool.result.content → gen_ai.tool.call.result
- mcp.tool.result.is_error → error.type
- mcp.request.id → jsonrpc.request.id
- mcp.transport → network.transport
- mcp.resource.protocol → network.protocol.name

Created 3 new attributes:
- gen_ai.prompt.name (OTel gen_ai registry, aliased from mcp.prompt.name)
- jsonrpc.request.id (OTel MCP common refs, aliased from mcp.request.id)
- jsonrpc.protocol.version (OTel MCP common refs)

27 Sentry-only attributes remain unchanged (mcp.client.*, mcp.server.*,
mcp.logging.*, mcp.progress.*, mcp.prompt.result.*, etc.) — these have
no OTel equivalent.

* fix(mcp): add reciprocal alias entries for MCP deprecations

The backfill deprecations on mcp.tool.name and mcp.tool.result.content
point to gen_ai.tool.name and gen_ai.tool.call.result respectively, but
the target attributes were missing the reciprocal alias entries. Add
mcp.tool.name and mcp.tool.result.content to the alias arrays of their
replacement attributes to maintain symmetric alias-group metadata.

Regenerated JS and Python attribute files to reflect the changes.

* fix(mcp): Add symmetric aliases and update name templates for deprecated MCP attributes

Fix CI failures caused by asymmetric alias relationships and deprecated
attribute references in name templates:

- Add reciprocal aliases to mcp.tool.result.content for the full alias
  group (gen_ai.tool.call.result, gen_ai.tool.message, gen_ai.tool.output)
- Add mcp.tool.result.content to gen_ai.tool.message and gen_ai.tool.output
  alias lists
- Add alias list to mcp.tool.name (gen_ai.tool.name, ai.function_call)
- Add mcp.tool.name to ai.function_call alias list
- Update mcp.json name templates to use gen_ai.tool.name and
  gen_ai.prompt.name instead of deprecated mcp.tool.name and mcp.prompt.name

* fix(jsonrpc): Change pii to 'maybe' for jsonrpc.protocol.version and jsonrpc.request.id

Address review feedback from loewenheim: string attributes should default
to pii 'maybe' unless scrubbing would cause product degradation.