> For the complete documentation index, see [llms.txt](https://docs.convai.com/api-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.convai.com/api-docs/plugins-and-integrations/convai-unity-sdk/features/multi-character-sessions/character-identity.md). # Character identity Reference for assigning Character IDs to characters sharing a Convai room, and the checks that catch two characters using one ID. Every `ConvaiCharacter` in a room needs its own Character ID. Two characters cannot share one, and the SDK checks for this both while editing the scene and when the room connects. ### Why an ID cannot be shared The SDK routes ownership, participants, and audio by Character ID. Two characters holding the same ID do not each get their own routing — the second collides with the first, and the room answers both through whichever one was registered first rather than keeping them separate. Duplicating a working character is the ordinary way a scene gets its second one, and the copy arrives holding the original's Character ID. This is the case both checks below exist for. ### Edit Mode warning on the Character inspector Select a `ConvaiCharacter` that shares its Character ID with another character in the loaded scenes, and its inspector shows an error box titled **Another character has this Character ID**: ``` '' in the loaded scenes uses this same ID. The SDK keys ownership, participants and audio by Character ID, so two characters sharing one collide instead of each getting their own — the room routes both to whichever was registered first. Give this character its own ID from the Convai dashboard. ``` The message names every other character sharing the ID, not only the first one found. The check runs whether or not a multi-character session is active — a duplicate ID is wrong in any scene, because the registry keys routing by it regardless of room shape. {% hint style="info" %} `Convai.ValidateSetup` reports the same conflict as an error, so a continuous integration run or an editor script can catch it without opening the Inspector. {% endhint %} ### Refusal when the room connects A room whose active, enabled characters include two with the same Character ID refuses to connect. The `ConvaiOperationException` carries this message: ``` '' and '' both use Character ID . Two characters in one room cannot share an ID — the SDK routes ownership, participants and audio by it, so they would collide rather than each being answered separately. Give each character its own Character ID from the Convai dashboard. ``` This check runs on both paths into a room's roster: the full cast submitted at connect, and a single character added later while the room is already up. Either way the room does not connect — or does not accept the addition — rather than connecting with the two characters colliding. ### Character ID format The **Character ID** field on `ConvaiCharacter` is validated independently of the duplicate check. An invalid value produces one of these messages in the Inspector: | Condition | Message | | ------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Field is empty | `Character ID is required. Copy it from your character's page on the Convai dashboard.` | | Leading or trailing whitespace | `Character ID has a space before or after it. Delete the extra spaces.` | | Wrong length | `Character ID should be 36 characters, and this one is . Copy the whole ID from the Convai dashboard.` | | Not a GUID | `Character ID is not in the expected form xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. Copy it again from the Convai dashboard — it is easy to pick up a character's name by mistake.` | Duplicate-ID comparison ignores case and surrounding whitespace, so `AB12…` and `ab12…` are treated as the same ID. A character with no ID is skipped by the duplicate check and reported by the format check above instead. ### Related {% content-ref url="/pages/iYCwUGyNwOPIaSoxu1mq" %} [How multi-character sessions work](/api-docs/plugins-and-integrations/convai-unity-sdk/features/multi-character-sessions/how-multi-character-sessions-work.md) {% endcontent-ref %} {% content-ref url="/pages/1ecP3hx3YP0V69UUKR6u" %} [Build your first multi-character session](/api-docs/plugins-and-integrations/convai-unity-sdk/features/multi-character-sessions/quick-start.md) {% endcontent-ref %} --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.convai.com/api-docs/plugins-and-integrations/convai-unity-sdk/features/multi-character-sessions/character-identity.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.