Reference

MCP errors and write recovery

Structured failures, CAS, receipts, retries and mount-specific recovery.

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Response model

MCP tools/call failures return tool-level results with isError and structured error:{code,message,...details}; these are distinct from JSON-RPC transport/protocol errors. The desktop helper separately returns JSON-RPC -32000 with data.code: E_APP_NOT_RUNNING for an unavailable app or JSON-RPC -32603 when HTTP has no body. Success commonly includes structured content and text content. There is no official per-tool output JSON Schema: consult each tool's documented source-grounded result contract, and treat optional fields as conditional. The compact response budget is 16,384 bytes.

Exact operational codes

Code

Meaning and action

E_ARGUMENT

Invalid/missing input, unknown key, selector conflict, or invalid cursor/limit. Correct the request; do not retry unchanged invalid input.

E_PATH

Path is outside an allowed local folder/mount. Use the exact mount key from gram_projects; never substitute its display name.

E_READ_ONLY

Approval or mount is read-only. Reads may continue; a write requires an already-authorized writable scope.

STALE_READ

Document moved during historical read. Read again at current state.

STALE_CURSOR

Cursor is bound to another document/revision/section. Get a fresh page/read cursor.

E_CURSOR

Cursor malformed. Obtain a replacement from the corresponding listing/read.

E_REQUEST_REUSE

The same ID is bound to a different intent. Do not retry the changed request under that ID; retry the original exact intent only to replay it, or use a new ID for a new intent.

COMMIT_UNKNOWN

Replacement was published but durability is uncertain. Retry only the identical patch with the same request ID; inspect persisted state before claiming success.

STORAGE_CONFLICT

Cloud provider state conflicted. Re-read persisted state before composing a new write.

PROVIDER_AUTH_REQUIRED

Provider authorization is needed. No successful remote write is implied.

E_STORAGE

Storage commit failed. Inspect receipt and sync status, then re-read before retrying.

E_INTEGRITY

History sequence/hash audit failed. Core rejects writes to corrupt history; do not repair by editing the trailer.

E_MIGRATION

Legacy data cannot be converted by the requested path. Preserve source and use the supported migration contract.

Other source-defined errors include E_CORE_UNAVAILABLE, E_TIMEOUT, E_CORE, E_INTERNAL, E_UNKNOWN_TOOL, E_CONTEXT_BUDGET, E_TOO_MANY_DOCUMENTS, E_TIME_NOT_RECORDED and E_REQUEST_ID. Read the returned code/details; codes are not interchangeable.

Safe CAS sequence

  1. Read current document identity {path,rev,hash}.

  2. Prepare one intended patch with that revision/hash, a unique 1–128-character request ID, and nonempty operations.

  3. The public tools expose no receipt tool. For an uncertain gram_patch, resend the exact same request_id and unchanged path, base_revision, expected_hash, and operations; Core replays the original receipt.

  4. If Core reports stale/CAS conflict, reread and rebase the human intent on the new content; send a new request ID.

  5. On mounted cloud writes, verify returned sync.state: synced; successful MCP completion alone is not the remote persistence check.

A request_id binds canonical intent, including document ID, operation, base_revision, expected_hash, operations, effective_at, and context. An A-to-B-to-A reversal has a different CAS base and is a different intent, so reusing the first ID returns E_REQUEST_REUSE.

Create and retry boundaries

gram_create has no request_id. If its response is uncertain, read the target path before further action. Creating at an existing path returns STALE_REVISION with Create target already exists; do not treat it as a patch or overwrite.

Only retry gram_patch by resending the exact same request_id and complete intent. The public MCP API has no standalone receipt tool. The shortened displayed hash maps to a full artifact hash held by the caller's gateway; if a short hash is no longer resolvable, reread rather than guessing.

Local/cloud boundary

Local document tools require the app's approved vault scope; profile and capabilities are available without document approval. Read-only approvals reject create/patch. Cloud tools open a caller-scoped workspace, use exact mount paths, and commit back to the provider. Cloud capability reports semantic search unavailable and auto uses lexical fallback; local semantic behavior is runtime-probed. Local mount sync may be pending; cloud successful writes report synced. No tool bypasses the caller's existing authority.

Exact source-backed error messages

Surface

Code

Actual message

Sources

MCP tool result

E_ARGUMENT

Unknown argument

thegram-vault/internal/mcp/gateway.go#335359731a3724bb0bf7a02093e3d7e1bbd93ccda3bbdff143b6178eec98a436

MCP tool result

E_CURSOR

Invalid list cursor

thegram-vault/internal/mcp/tools_common.go#f243590ff0ab46a241c752ae104c538e5064c869525209dfc7219572d6d5523c

MCP tool result

E_CURSOR

Invalid section cursor

thegram-vault/internal/mcp/memory.go#cf97b451501c97d5db3c43836171a65ce221b9105d1b3c75ae58ccefc93e72e1

MCP tool result

E_CURSOR

Invalid changes cursor

thegram-vault/internal/mcp/memory.go#cf97b451501c97d5db3c43836171a65ce221b9105d1b3c75ae58ccefc93e72e1

MCP tool result

E_CURSOR

Invalid context cursor

thegram-vault/internal/mcp/tools_entity.go#04d41ed2634d5904fa812be53c92c70a06403d78334890b9791c168b8f89c9f0

MCP tool result

E_CURSOR

Invalid state cursor

thegram-vault/internal/mcp/tools_history.go#c2d2b98e94a1cebbc9aadae0e931500c109b61fe44e90ad2f9e1bc6b76e499c8

desktop JSON-RPC -32000

E_APP_NOT_RUNNING

Thegram is not running. Open the Thegram app, then retry.

thegram-desktop/Helper/ThegramMCP.swift#87b7fdb6a576da59e84d86ae32624e452f5da7e3c4138b6f539374437556e6dd

desktop JSON-RPC

JSON-RPC -32603

Thegram answered HTTP \(response.status) with no body

thegram-desktop/Helper/ThegramMCP.swift#87b7fdb6a576da59e84d86ae32624e452f5da7e3c4138b6f539374437556e6dd

MCP tool result

STALE_READ

The document changed while it was read; read again

thegram-vault/internal/mcp/tools_common.go#f243590ff0ab46a241c752ae104c538e5064c869525209dfc7219572d6d5523c

MCP tool result

STALE_READ

The document was replaced while it was read

thegram-vault/internal/mcp/tools_history.go#c2d2b98e94a1cebbc9aadae0e931500c109b61fe44e90ad2f9e1bc6b76e499c8

MCP tool result

STALE_CURSOR

The documents changed since this cursor; list again

thegram-vault/internal/mcp/tools_common.go#f243590ff0ab46a241c752ae104c538e5064c869525209dfc7219572d6d5523c

MCP tool result

STALE_CURSOR

The documents changed since this cursor; ask again without cursor

thegram-vault/internal/mcp/memory.go#cf97b451501c97d5db3c43836171a65ce221b9105d1b3c75ae58ccefc93e72e1

MCP tool result

STALE_CURSOR

Cursor belongs to another document or revision

thegram-vault/internal/mcp/tools_history.go#c2d2b98e94a1cebbc9aadae0e931500c109b61fe44e90ad2f9e1bc6b76e499c8

MCP tool result

STALE_CURSOR

The cursor belongs to another document, revision or section

thegram-vault/internal/mcp/memory.go#cf97b451501c97d5db3c43836171a65ce221b9105d1b3c75ae58ccefc93e72e1

MCP tool result

E_REQUEST_REUSE

request_id belongs to another intent

thegram-format/native/api.rs#a7e13ec4b422ae4907c7d7eac481267103f9b4b86248e706a82251cc597a5e02

MCP tool result

E_REQUEST_ID

Nonempty request_id required

thegram-format/native/api.rs#a7e13ec4b422ae4907c7d7eac481267103f9b4b86248e706a82251cc597a5e02

MCP tool result

E_CAS_REQUIRED

base_revision required

thegram-format/native/api.rs#a7e13ec4b422ae4907c7d7eac481267103f9b4b86248e706a82251cc597a5e02

MCP tool result

E_CAS_REQUIRED

Create requires explicit null base_revision

thegram-format/native/api.rs#a7e13ec4b422ae4907c7d7eac481267103f9b4b86248e706a82251cc597a5e02

MCP tool result

STALE_REVISION

Accepted revision or hash changed

thegram-format/native/temporal.rs#a143cc67c4518c4599f96af9565ae765c1dcdc770d694b13a8fdc08a03c69c0e

Core import-source CAS

STALE_REVISION

Accepted revision or hash changed; preserve both originals

thegram-format/native/temporal.rs#a143cc67c4518c4599f96af9565ae765c1dcdc770d694b13a8fdc08a03c69c0e

MCP tool result

STALE_REVISION

Artifact changed during transaction

thegram-format/native/store.rs#3bd54253eeee764c2cdf1d3dc1e9c0f4f1d9f96fbd75c66171d96b19a342addc

MCP tool result

STALE_REVISION

Create target already exists

thegram-format/native/store.rs#3bd54253eeee764c2cdf1d3dc1e9c0f4f1d9f96fbd75c66171d96b19a342addc

MCP tool result

COMMIT_UNKNOWN

Replacement published but durability is uncertain: {e}

thegram-format/native/store.rs#3bd54253eeee764c2cdf1d3dc1e9c0f4f1d9f96fbd75c66171d96b19a342addc

MCP tool result

COMMIT_UNKNOWN

Marker observed but durability not confirmed: {e}

thegram-format/native/store.rs#3bd54253eeee764c2cdf1d3dc1e9c0f4f1d9f96fbd75c66171d96b19a342addc

MCP tool result

STORAGE_CONFLICT

remote file changed since it was read

thegram-vault/internal/mcp/workspace.go#9de8ccbfe796301fd9406f7b78d775da520dfb77127aea2a3caf499391143ad9

MCP tool result

STORAGE_CONFLICT

remote file changed and local restoration failed

thegram-vault/internal/mcp/workspace.go#9de8ccbfe796301fd9406f7b78d775da520dfb77127aea2a3caf499391143ad9

MCP tool result

E_STORAGE

workspace storage is not configured

thegram-vault/internal/mcp/workspace.go#9de8ccbfe796301fd9406f7b78d775da520dfb77127aea2a3caf499391143ad9

MCP tool result

PROVIDER_AUTH_REQUIRED

Google Drive must be reconnected

thegram-vault/internal/mcp/workspace.go#9de8ccbfe796301fd9406f7b78d775da520dfb77127aea2a3caf499391143ad9

MCP tool result

E_PATH

Absolute paths are outside the approved folder

thegram-vault/internal/mcp/paths.go#754797578ba9858e6db8707f17ca9ceed82914215e83e00e437a05e925bff936

MCP tool result

E_PATH

Path does not start with a mounted collection

thegram-vault/internal/mcp/paths.go#754797578ba9858e6db8707f17ca9ceed82914215e83e00e437a05e925bff936

MCP tool result

E_PATH

Path is outside the approved folders

thegram-vault/internal/mcp/paths.go#754797578ba9858e6db8707f17ca9ceed82914215e83e00e437a05e925bff936

MCP tool result

E_PATH

Path is outside an approved folder or hidden

thegram-vault/internal/mcp/paths.go#754797578ba9858e6db8707f17ca9ceed82914215e83e00e437a05e925bff936

MCP tool result

E_PATH

Vault mounts support writes only to top-level documents

thegram-vault/internal/mcp/paths.go#754797578ba9858e6db8707f17ca9ceed82914215e83e00e437a05e925bff936

MCP tool result

E_READ_ONLY

This mounted folder is read-only to agents

thegram-vault/internal/mcp/paths.go#754797578ba9858e6db8707f17ca9ceed82914215e83e00e437a05e925bff936

r5 · · Portal-reference-finalize

Structured failures, CAS, receipts, retries and mount-specific recovery.

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.gram language specification
Current rich document specification
Current History/6 specification