helpful in the future if we want more granularity for requesting
escalated permissions:
e.g when running in readonly sandbox, model can request to escalate to a
sandbox that allows writes
Previously, we were running into an issue where we would run the `shell`
tool call with a timeout of 10s, but it fired an elicitation asking for
user approval, the time the user took to respond to the elicitation was
counted agains the 10s timeout, so the `shell` tool call would fail with
a timeout error unless the user is very fast!
This PR addresses this issue by introducing a "stopwatch" abstraction
that is used to manage the timeout. The idea is:
- `Stopwatch::new()` is called with the _real_ timeout of the `shell`
tool call.
- `process_exec_tool_call()` is called with the `Cancellation` variant
of `ExecExpiration` because it should not manage its own timeout in this
case
- the `Stopwatch` expiration is wired up to the `cancel_rx` passed to
`process_exec_tool_call()`
- when an elicitation for the `shell` tool call is received, the
`Stopwatch` pauses
- because it is possible for multiple elicitations to arrive
concurrently, it keeps track of the number of "active pauses" and does
not resume until that counter goes down to zero
I verified that I can test the MCP server using
`@modelcontextprotocol/inspector` and specify `git status` as the
`command` with a timeout of 500ms and that the elicitation pops up and I
have all the time in the world to respond whereas previous to this PR,
that would not have been possible.
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/6973).
* #7005
* __->__ #6973
* #6972
This PR introduces an extra layer of abstraction to prepare us for the
migration to execpolicy2:
- introduces a new trait, `EscalationPolicy`, whose `determine_action()`
method is responsible for producing the `EscalateAction`
- the existing `ExecPolicy` typedef is changed to return an intermediate
`ExecPolicyOutcome` instead of `EscalateAction`
- the default implementation of `EscalationPolicy`,
`McpEscalationPolicy`, composes `ExecPolicy`
- the `ExecPolicyOutcome` includes `codex_execpolicy2::Decision`, which
has a `Prompt` variant
- when `McpEscalationPolicy` gets `Decision::Prompt` back from
`ExecPolicy`, it prompts the user via an MCP elicitation and maps the
result into an `ElicitationAction`
- now that the end user can reply to an elicitation with `Decline` or
`Cancel`, we introduce a new variant, `EscalateAction::Deny`, which the
client handles by returning exit code `1` without running anything
Note the way the elicitation is created is still not quite right, but I
will fix that once we have things running end-to-end for real in a
follow-up PR.
