message_update
Replace one exact span of text inside your own earlier Mattermost message, leaving the rest of it untouched.
| Namespace | message |
|---|---|
| Effect | external_write |
| Approval | not required |
| Presence | not required |
| Privacy | platform_message |
| Version | v2 |
What the model reads
Replace one exact span of text inside your own earlier Mattermost message, leaving the rest of it untouched. oldText must appear exactly once in that message; copy it verbatim from a message_search preview or from the message you sent. This is the tool for every correction to something you already posted — when the user points out a mistake, fix that message instead of posting a correction as a new one. It runs immediately without asking the user to confirm, because it can only change text you quoted. If oldText does not match, the call fails without changing anything and returns the message as it currently reads, so retry with a span copied from that. To rewrite a long message wholesale, read it in full first with message_search messageIDs and quote what you read.