fix: allow more attachments without raising the image payload budget

[Bil0000]

T3 rejects a ninth attachment before it reaches a provider. Allow up to 100 attachments across web, desktop, mobile, queued drafts, and question answers. Keep the existing 10 MiB image and 50 MiB file limits, with an 80 MiB aggregate image budget: the same maximum image bytes previously possible with eight 10 MiB images.

The count is a T3 resource guard, not a claim that every provider accepts 100 images. Existing adapter guards remain in place. Validate decoded image sizes before writing each upload and remove newly written files on failure. Images labeled as generic files count toward the image budget; videos and other path-only files do not.

Harness	Checked path and limits
Codex	App-server input array has no count maximum. An upstream report describes a 50-image conversation ceiling; it is not a universal per-turn guarantee.
Claude	Agent SDK accepts image blocks. API docs publish 100/600 images depending on context size, a 32 MB request limit, and stricter dimensions above 20 images. Those are not verified subscription-route limits.
Cursor	ACP has no prompt-array count maximum; Cursor ACP docs do not establish a separate count ceiling.
Grok	ACP has no count maximum. Public image API lists 20 MiB per image and no image count cap; Grok Build subscription parity is unconfirmed.
OpenCode	SDK prompt parts have no count cap. T3 keeps its existing 20 MiB native-file cutoff and path fallback. Model limits still apply.
Antigravity	T3 keeps its existing 1 MiB text, 10 MiB image, 20 MiB audio, and 50 MiB total attachment guards. These are adapter guards, not independently verified upstream limits.

Videos remain file-path context for Codex, Claude, Cursor, Grok, and OpenCode, with the existing 50 MiB upload limit. Antigravity still rejects video. This does not add native video input.

Verified with 839 focused tests, including all six adapter suites, upload rollback, 100/101 attachment boundaries, the 80 MiB image boundary, web drafts, and mobile pickers/sharing. Contracts typecheck, targeted lint, and formatting pass.

Limits: provider/model limits, prior conversation images, and payload overhead can still reject a request below these T3 bounds. No universal SDK/ACP count limit was established, so this does not invent one or guarantee subscription-route capacity from public API docs. Provider tests use mocks; no authenticated high-volume run was performed. UI media remains unavailable because the built-in Browser panel cannot reach the isolated loopback dev port (ERR_CONNECTION_REFUSED).

Model: GPT-6. Harness: OpenAI Codex.

Summary by CodeRabbit

• New Features
  • Increased the attachment limit to 100 files per message and provider turn.
  • Added an 80 MiB combined limit for image attachments while retaining the 10 MiB per-image limit.
  • Applied the updated limits to question attachments and composer workflows.
  • Continued supporting other files up to 50 MiB each.
• Documentation
  • Updated attachment guidance, including image, video, and provider-specific limitations.

[macroscopeapp]

Approvability

Verdict: Not approved

Macroscope's review found this PR not approvable — The shared attachment default changes from 8 to 100 across client and server paths, with new aggregate image-budget validation and upload cleanup behavior. This is a broad user-facing product-default change with provider-limit implications, so it warrants human review.

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[macroscopeapp]

All clear

^{Posted via Macroscope — Effect Service Conventions}

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 93e414e and 25ec8e8.

📒 Files selected for processing (7)

• apps/mobile/src/lib/composerFiles.test.ts
• apps/mobile/src/state/use-composer-drafts.test.ts
• apps/server/src/orchestration/Normalizer.attachments.test.ts
• docs/user/composer.md
• docs/user/question-attachments.md
• packages/contracts/src/orchestration.ts
• packages/contracts/src/provider.test.ts

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📝 Walkthrough

Walkthrough

The change raises the attachment limit to 100, adds an 80 MiB combined image limit, centralizes validation, checks decoded images during normalization, and updates mobile tests and documentation.

Changes

Attachment limit validation

Layer / File(s)	Summary
Shared attachment validation packages/contracts/src/orchestration.ts, packages/contracts/src/provider.ts, packages/contracts/src/provider.test.ts	The provider limit increases to 100 attachments. Image attachments share an 80 MiB total limit, while individual images remain limited to 10 MiB. Provider input validation uses the shared helper.
Command normalization and cleanup apps/server/src/orchestration/Normalizer.ts, apps/server/src/orchestration/Normalizer.attachments.test.ts	Both supported command types use the shared limit check. Decoded attachments are checked during normalization. Persisted image paths are tracked for cleanup when validation fails.
Client tests and attachment documentation apps/mobile/src/lib/composerFiles.test.ts, apps/mobile/src/state/use-composer-drafts.test.ts, docs/user/composer.md, docs/user/question-attachments.md	Mobile tests and documentation use the 100-attachment limit and describe the image-size, file-size, provider, model, and video rules.

Priority: ➖ Normal

Estimated code review effort: 3 (Moderate) | ~25 minutes

Change: Feature

Sequence Diagram(s)

sequenceDiagram
  participant ProviderSendTurnInput
  participant normalizeDispatchCommand
  participant getProviderAttachmentLimitError
  participant AttachmentStorage
  ProviderSendTurnInput->>getProviderAttachmentLimitError: validate attachment count and image bytes
  normalizeDispatchCommand->>getProviderAttachmentLimitError: validate command attachments
  normalizeDispatchCommand->>AttachmentStorage: decode and persist attachments
  normalizeDispatchCommand->>getProviderAttachmentLimitError: validate decoded attachments
  normalizeDispatchCommand->>AttachmentStorage: remove claimed paths after validation failure

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Suggested reviewers: t3dotgg, juliusmarminge

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 7 files. (2 skipped: 2 …	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly summarizes the main change: increasing attachment capacity without increasing the image payload budget.
Description check	✅ Passed	The description provides detailed change scope, rationale, limits, provider considerations, validation results, and UI context. It does not use the template headings or checklist, but it contains the …

Full details: Docstring Coverage

Explanation

Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 7 files. (2 skipped: 2 unsupported.)

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[coderabbitai]

Actionable comments posted: 1

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🤖 Prompt to fix review comments

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only still-valid issues, skip the rest with a brief reason, keep changes
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Inline comments:
In `@apps/server/src/orchestration/Normalizer.ts`:
- Line 295: Update the inline-image persistence flow in Normalizer so decoded
image bytes are tracked against the aggregate 20 MiB image limit before each
writeFile call. Reject through getProviderAttachmentLimitError (or the existing
equivalent) as soon as the next decoded image would exceed the limit, while
preserving per-image and attachment-count validation.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository: pingdotgg/t3code/.coderabbit.yaml

Review profile: CHILL

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Run ID: a0ad8301-374e-41d5-ba92-12887e035200

📥 Commits

Reviewing files that changed from the base of the PR and between b44c1ce and 51b7118.

📒 Files selected for processing (9)

• apps/mobile/src/lib/composerFiles.test.ts
• apps/mobile/src/state/use-composer-drafts.test.ts
• apps/server/src/orchestration/Normalizer.attachments.test.ts
• apps/server/src/orchestration/Normalizer.ts
• docs/user/composer.md
• docs/user/question-attachments.md
• packages/contracts/src/orchestration.ts
• packages/contracts/src/provider.test.ts
• packages/contracts/src/provider.ts

Included review availability: Your plan provides up to 10 included reviews per hour; 9 remain after this review.

[Bil0000]

The docstring-coverage warning does not require a code change here. The task explicitly excludes new docstrings, and the shared helper is covered by focused behavior tests. The actionable image-write finding is fixed in 6115d28 and its thread is resolved.

[macroscopeapp]

All clear

^{Posted via Macroscope — Effect Service Conventions}

[shivamhwp]

Approved by me. Would still like Julius to take a look.

Testing passed:

• Sent 100 files through the web UI and received a Codex response.
• Confirmed the 101st file is rejected without losing existing attachments.
• Verified draft reload and attachment removal/replacement.
• All 12 API checks and 749 focused tests passed, including size limits and upload cleanup.

Full test report

100 files sent successfully, with Codex’s response:

The 101st attachment is rejected while the existing 100 remain:

The live Codex test used small text files. High-volume image input and native desktop/mobile remain unverified.