Reference

Error codes

Every code Sidekick can surface, what it means, and what to do about it. Filter by category or search by code.

32 codes

NO_CEP

CEP

CSInterface or window.__adobe_cep__ is missing. Sidekick is running outside AE.

Fix: Run inside AE. If it appears in production, the install is corrupt – reinstall the .zxp.

NO_CS

CEP

CSInterface unreachable while opening or closing an extension.

Fix: Reopen the panel; reinstall if it persists.

EMPTY

CEP

evalScript callback fired with empty string. Usually a CEP input race during typing.

Fix: Retry once.

EVAL_ERROR

CEP

AE's ExtendScript engine threw. CEP returned the literal 'EvalScript error.'

Fix: Click Details on the response to read the underlying jsx error. Common causes: typo in a generated expression, or a property reference that disappeared between Send and Apply.

UNDEFINED

CEP

jsx host returned the literal string "undefined" – function is not loaded.

Fix: Reopen AE so the panel re-loads its jsx host. Reinstall if it persists.

BAD_SHAPE

CEP

jsx response parsed but missing the expected ok field.

Fix: Bug – file an issue with the raw response.

PARSE

CEP

jsx response or LLM JSON could not be parsed.

Fix: Retry. If recurring, the schema is drifting – switch model or file an issue.

THROW

CEP

evalScript or the open/close extension call threw client-side.

Fix: Retry. Reopen panel if persistent.

TIMEOUT

CEP

jsx call exceeded 30 seconds.

Fix: Cancel any long-running script and retry.

NO_COMP

No active composition in AE.

Fix: Open or focus a composition.

NO_LAYER

Layer ID not found in active comp (likely deleted or reordered).

Fix: Reselect the layer and resubmit.

NO_EFFECTS

Layer's Effect Parade is unreachable (e.g. on a locked layer).

Fix: Unlock the layer or pick a different one.

ADD_FAILED

Effects.addProperty(matchName) returned null.

Fix: Verify your AE version supports the control's matchName. File a bug if it does.

BAD_TYPE

Unknown control type passed to addControlToLayer.

Fix: Bug in caller – file an issue.

BAD_PATH

matchNamePath JSON invalid or empty.

Fix: Re-pick the property and resubmit.

NO_PROP

matchNamePath traversal didn't land on a property.

Fix: Refresh selection. The property may have moved.

NOT_EXPR_CAPABLE

Property doesn't accept expressions (e.g. a property group).

Fix: Pick a leaf property like Position or Scale.

NO_FOLDER

Cannot resolve ~/Documents/Adobe/After Effects {year}/Scripts/.

Fix: Check folder permissions on your AE Documents folder.

OPEN_FAILED

ExtendScript File.open returned false. Disk full or permissions denied.

Fix: Check the Scripts folder ACL and free disk space.

BAD_INPUT

Caller passed a non-string where a string was required.

Fix: Bug in caller – file an issue.

CANCELLED

User clicked Cancel on a native AE confirm dialog.

Fix: Not an error. Re-trigger the action if you intended to proceed.

HTTP_4xx / 5xx

Provider

AI provider returned a non-2xx response. 401/403 means auth, 429 is rate-limit, 5xx is server-side.

Fix: 401/403 – verify your API key in Settings. 429 – wait and retry, or switch model. 5xx – retry, or check the provider's status page.

NETWORK

Provider

fetch threw before getting a response (DNS, offline, TLS).

Fix: Check connectivity. CSP whitelists provider endpoints, so a corporate proxy can also be the cause.

ABORTED

Provider

User cancelled an in-flight stream.

Fix: Not an error. Resubmit if intended.

BAD_REQUEST

Provider

Anthropic-side request build failure.

Fix: Bug – file an issue with your prompt.

NO_OBJECT

Parser

Empty response or no JSON object found.

Fix: Likely a token-cap or safety-filter hit. Retry, raise the model's budget, or switch provider.

VALIDATION

Parser

LLM JSON valid but failed schema validation.

Fix: Retry. If persistent, the model is drifting – pick a stronger model.

ae

Pipeline

Pipeline-level: AE selection read failed.

Fix: See the underlying AE code (NO_COMP, NO_LAYER, etc.).

llm

Pipeline

Provider failed; non-network, non-config.

Fix: Retry, or check the provider's status page.

network

Pipeline

Provider HTTP 4xx/5xx other than auth, or NETWORK/ABORTED.

Fix: Check connectivity and retry.

config

Pipeline

Auth failure (401/403) or no provider configured.

Fix: Open Settings, verify the API key and that the provider is enabled.

parse

Pipeline

LLM output couldn't be parsed.

Fix: Retry. Use the Details toggle on the response to see the raw output.