docs: add mcp and skill session config

[NathanFlurry]

No description provided.

[railway-app]

🚅 Deployed to the sandbox-agent-pr-106 environment in sandbox-agent

Service	Status	Web	Updated (UTC)
website	😴 Sleeping (View Logs)	Web	Feb 6, 2026 at 8:38 pm

[NathanFlurry]

• docs: add mcp and skill session config #106 👈 (View in Graphite)
• main

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[claude]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.

[claude]

Code Review

Found 4 issues that need attention:

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Issue 1: Missing HTTP test coverage for mkdir and stat endpoints

CLAUDE.md Violation: Line 36 requires "When changing API routes, ensure the HTTP/SSE test suite has full coverage of every route."

The PR adds 8 new filesystem endpoints, but the test suite at server/packages/sandbox-agent/tests/http/fs_endpoints.rs only tests 6 of them:

✅ Tested:

• GET /v1/fs/entries
• GET /v1/fs/file
• PUT /v1/fs/file
• DELETE /v1/fs/entry
• POST /v1/fs/move
• POST /v1/fs/upload-batch

❌ Not tested:

• POST /v1/fs/mkdir
• GET /v1/fs/stat

These endpoints need test coverage added to comply with CLAUDE.md requirements.

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Issue 2: set_session_overrides unconditionally clears model and variant

File: server/packages/sandbox-agent/src/router.rs lines 1659-1660

The behavior of set_session_overrides changed to unconditionally assign model and variant:

session.model = model;
session.variant = variant;

This erases existing session settings when None is passed. The previous behavior only updated when Some:

if let Some(model) = model { session.model = Some(model); }
if let Some(variant) = variant { session.variant = Some(variant); }

Impact: When opencode_compat.rs calls ensure_backing_session with None values (common for follow-up messages), the session's model and variant are cleared. This causes the agent to fall back to default model instead of the user-configured one.

Suggested fix: Restore the conditional assignment logic to preserve existing values when None is passed.

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Issue 3: OpenAPI spec includes removed variants field in AgentCapabilities

Files:

• docs/openapi.json line 1076 (in required array)
• docs/openapi.json lines 1135-1137 (field definition)

The Rust AgentCapabilities struct lines 3788-3808 does not have a variants field, but the OpenAPI spec lists it as required.

Impact:

• The TypeScript SDK has variants: boolean as a non-optional field, but the server never serializes it
• Clients validating against the OpenAPI spec will fail
• TypeScript consumers will get undefined at runtime despite the type saying boolean

Suggested fix: Regenerate docs/openapi.json and sdks/typescript/src/generated/openapi.ts from the Rust structs to remove the variants field.

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Issue 4: OpenAPI spec includes removed defaultVariant field in AgentModelInfo

File: docs/openapi.json lines 1249-1251

The Rust AgentModelInfo struct lines 3762-3770 only has three fields: id, name, and variants. The defaultVariant field does not exist.

However, the OpenAPI spec and TypeScript types still include defaultVariant?: string | null.

Impact: The OpenAPI spec documents a field that the server never returns, creating a schema mismatch.

Suggested fix: Regenerate docs/openapi.json and sdks/typescript/src/generated/openapi.ts from the Rust structs to remove the defaultVariant field.

[graphite-app]

Merge activity

• Feb 6, 2:34 PM UTC: NathanFlurry added this pull request to the Graphite merge queue.
• Feb 6, 2:34 PM UTC: NathanFlurry removed this pull request from the Graphite merge queue.