How to Answer Questions Across Slack, Drive and Notion

Verdict

Glean is the broader-coverage option for this Slack, Google Drive and Notion workflow. Guru is the governed-source option when teams will own, verify and retire canonical answers. This is a feature-fit recommendation, not a measured relevance ranking. The exception is decisive: Glean's indexed Notion content is visible to every Glean user who can access that connector because Notion does not expose the page-sharing data its crawler needs. If Notion contains audience-specific material, connect only all-company pages, separate audiences by connector instance or use eligible per-user retrieval.

This is an implementation guide, not another vendor shortlist. See the AI workplace search tools guide for category choice and Glean vs Guru for the broader product decision. We have not run an authenticated cross-vendor benchmark; connector behavior below comes from first-party documentation checked October 23, 2026.

Permission and freshness matrix

Configure Glean without flattening access

For Slack, set up both the native connector and Slack Real Time Search. RTS retrieves message bodies live from Slack rather than storing them in the RTS index. Admins decide whether private channels and private messages are eligible; each user then authorizes access. Use channel inclusion or exclusion rules for HR, legal and incident rooms. Email-to-channel messages are a documented gap, so do not assume every visible Slack item is retrievable.

For Drive, use a service account with domain-wide delegation and the required read-only scopes. Glean indexes Docs, Sheets, Slides, folders and other files from personal and shared drives. Its Drive documentation says access changes are included in the 10-minute activity crawl and group changes in the hourly identity crawl, with a three-hour incremental crawl as backup. Test the exception for files shared as “anyone with the link” or to the domain: Glean documents extra discoverability conditions, including prior access, a searchable-domain setting, a shared Slack link or a pin. Files with bodies above 16 MB are metadata-only.

For Notion, split the corpus before connecting it. Glean indexes pages, databases and nested blocks shared with its integration, but its setup warning says Notion does not supply user-level page sharing. Share only content suitable for every user who can access that connector instance. For group-level separation, use separate Notion connector instances and restrict connector visibility. For per-user retrieval, use Live Mode, noting that it is beta, must be enabled for an eligible connection, and does not change the indexed corpus. The setup can also expose read and write tools; turn write tools off for a retrieval-only pilot. That distinction belongs in the security review.

Configure Guru around explicit source ownership

Treat Slack ingestion and answering inside Slack as two separate controls. A Slack source indexes selected channels after the Guru app is invited. Inherited access requires a Slack admin; Guru Groups can expose the source independently of Slack membership. Then assign a Source Owner. If a Knowledge Agent posts answers in a Slack channel, enable “Limit responses to sources shared with All Members” unless every channel member may read the generated text. Guru warns that with this control disabled, the answer is visible to the whole channel even when some readers cannot open its underlying source.

For Drive, choose the access mode deliberately. Guru-managed access indexes what the authenticating account can see, then controls visibility with Guru Groups; the original Drive link still checks Google access. Single-user inherited access also indexes only that account's visible files. For full company coverage, domain-wide delegation impersonates users across personal and shared drives while preserving their Drive permissions. A shortcut is searchable only when its original file is inside an authorized drive and the required access exists.

For Notion, the current Guru setup uses OAuth, selected pages or Teamspaces and Guru Groups. Pages, database structure, rows and nested blocks are supported. The guide does not document inherited Notion page permissions, so mirror your intended audiences in Guru and test child pages. Guru also documents a connection failure risk when the same Notion account authenticates multiple separate sources; extend one connection or use different accounts.

Guru says most sources are checked several times daily, initial indexing can take days and timing varies by source and volume. Slack is the published exception at near-real-time indexing. Do not turn the general schedule into a Drive or Notion SLA; measure both.

Require citations, then inspect them

Glean shows inline citations, source previews and a source list when Assistant actually retrieves company content. Its citation guide says Fast mode can skip retrieval, “No sources” uses model knowledge, and deep links vary by connector and admin settings. Select company sources for evaluation prompts and use Thinking mode where available; the setup advice specifically names Customer Key deployments. Open the original item rather than treating a citation as verification.

Guru answers link to cited sources and expose Answer Details with sources consulted and search terms. That is useful for separating a retrieval miss from a synthesis error. Verification status is a governance signal, not proof the source claim is correct. For either product, score whether each sentence is supported by the cited passage, not whether an answer contains citation-shaped links.

Run a pilot that can fail

Create three identities: ordinary employee, restricted-group member and recently revoked user. Prepare nine questions: two direct lookups and one cross-source synthesis anchored in each app. Run all nine under each identity for 27 checks. Include one stale policy, one deleted item and one conflicting Slack-versus-Notion answer.

Record source recall, answer correctness, citation support, edit-to-answer delay, revoke-to-hide delay and delete-to-hide delay. Repeat after 15 minutes, three hours, six hours and three days. A pass requires zero restricted-source exposure, an opened citation supporting every consequential claim, and an explicit “not found” when evidence is absent. Keep screenshots and source IDs for every failure.

Pricing should come after that gate. Glean Core Suite is per user per month and includes connectors, but publishes no seat amount. Core advanced AI uses Model Hub usage; the separate Enterprise Flex plan meters advanced capabilities with FlexCredits. Guru now sells a tailored platform-plus-expertise package and publishes no comparable seat price. Request a quote for the tested population, implementation, AI usage and ongoing connector ownership.

One community report reinforces the operating risk, not the ranking. In a May 26, 2026 r/SaaS post, u/sibraan_ said a 400-person services firm evaluated Salesforce, SharePoint, Slack, client files and meeting notes. The author found Glean effective for locating known files and Guru's verification useful but too dependent on documentation discipline for their team. This is anonymous, self-reported evidence, not our test.

Continue the rollout

• Search company knowledge with AI
• Build an internal AI knowledge base
• Glean profile
• Guru profile

Sources & further reading

• Glean Slack Real Time Search
• Glean Slack inclusion and exclusion rules
• Glean Google Drive overview and crawl schedule
• Glean Google Drive permission exceptions
• Glean Notion overview
• Glean Notion setup and permission limit
• Glean citations
• Glean Enterprise Flex pricing
• Glean Core Suite pricing
• Guru Slack source setup
• Guru Google Drive source setup
• Guru Notion source setup
• Guru source access and sync behavior
• Guru citations and Answer Details
• Guru Slack answer visibility
• Guru pricing
• Workplace-search evaluation by u/sibraan_