The terminal in Devin Desktop can assemble a command from a phrase in natural language, and this removes a familiar pain - recalling the exact syntax of a rare utility. The temptation is right here: since the command was generated by a tool, it is taken for correct and run. But a generated command is a suggestion, not a guarantee, and trusting it by the fact of generation is the main risk.
Let us first sort out what the terminal actually gives. With Cmd/Ctrl+I it turns a description of intent into a command line right in the terminal. A selection plus Cmd/Ctrl+L sends a piece of output - for example, a stack trace - to the agent as context. The active terminal can be attached to the conversation via @-mention so the agent can reason about what is happening in it. These are three different actions: generation, sending output and sending the terminal itself.
The key distinction is that generation does not mean safety. The model assembles a syntactically correct command from your description, but it does not know your environment: which aliases substitute names, what the variables equal, which directory you stand in, what a glob will expand to and where the output redirection will go. A syntactically correct command may do something quite other than you meant, and the terminal will execute it literally.
Hence a short check before running, not after. Expand aliases and variables to their real values. Confirm the working directory. Read what exactly the glob will capture and where the redirection will go. Look at the network address if the command reaches out somewhere. And separately ask yourself whether the command has an irreversible effect - a deletion, an overwrite, a push, a deploy. A minute of such expansion is cheaper than any rollback.
Next begins a confusion worth its own analysis: the words "allow" and "deny" here belong to two different models. Auto-execution levels and the allow/deny lists described on the terminal page relate to Cascade. Devin Local does not use them - it has its own permission model by tool type: read, write, execution, network fetch and MCP. The same-sounding setting lives in two different systems.
The difference is behavioral, not cosmetic. In Cascade a deny list does not block a command outright but triggers a confirmation prompt - the last word belongs to the human at the moment of running. In Devin Local an explicit deny blocks the action: it does not ask, it does not allow. So carrying an expectation from Cascade that "it will ask anyway" into Devin Local, you either hit a hard prohibition where you expected a dialog or, conversely, leave on allow what the old model would have prompted for.
Why two models are kept at once rather than one. Cascade carries the legacy of its era with auto-execution levels and command lists, and old processes on it keep working. Devin Local was rewritten around explicit permissions by tool type, where a prohibition is a prohibition and not a polite question. Combining them during the transition period is the price of not breaking working settings in a single day; the payment for it is the duty to know whose model applies in the current tab.
The cost of ignoring this distinction is a command executed that you did not expect. A dangerous line accepted as "generated, therefore safe" wipes the wrong directory or sends a request to the wrong place. A deny understood the Cascade way as "it will ask" silently blocks the needed action in Devin Local - and you lose time looking for a dialog that does not exist. Both outcomes follow from one thing: the command and the permissions were judged in the wrong model.
You should verify in two ways. Before running - by expanding the command into real values, as above; this catches the intent. After - by looking at the effect: was the right directory changed, did the right address respond, did the expected return code come back. And before both steps - confirm which agent runs the tab and therefore whose permission model applies in it. Three glances remove almost all the "why did it do that".
In the Cascade model itself the auto-execution levels are not binary, and knowing them helps even during migration: from full manual confirmation, through an allowlist and a mode where the agent judges the risk itself and only on premium models, to a variant that executes everything except what is denied. In teams an administrator can cap the maximum level and set shared lists. Devin Local does not inherit these levels - all the more reason not to carry their logic over to its permissions by tool type.
The typical failures are recognizable. You ran a generated command without looking - and the glob captured too much. You expected a deny to prompt in Devin Local - and did not understand why the action simply did not happen. You configured allow/deny in Cascade and decided it concerns Devin Local - two systems, one setting does not carry over. The common sign: the command was run or the setting was set without naming either the environment under the command or the agent under the tab. Name them first, and the terminal stops surprising you.