fix: add persistent cost to prevent under-reporting spent value - #7763

IdrisGit · 2026-01-11T08:19:33Z

What does this PR do?

This PR adds a persistent cost field to sessions to fix incorrect cost reporting in the sidebar when sessions exceed 100 messages. Previously, cost was calculated from the last 100 messages only, causing under-reporting for long sessions.

Key changes:

Added cost field to Session schema
Sessions now accumulate cost incrementally when assistant messages complete
Sidebar reads cost directly from session metadata instead of summing messages
Forked sessions inherit parent's accumulated cost
Added startup migration to backfill existing sessions

How did you verify your code works?

Verified with before/after testing on the same long session:

v1.1.12: Sidebar showed $0.12 (incorrect - last 100 messages only)
Local build: Sidebar shows $1.61 (correct - accumulated total cost)
Used local build to work on an issue in the same session, cost is being accumulated correctly.

OpenCode v1.1.12

OpenCode local

Fixes #7767 #6989

…iving from the messages array max 100 messages are kept in the store/memory which leads to misreporting of the actual spend value

github-actions · 2026-01-11T08:19:48Z

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

Please:

Open an issue describing the bug/feature (if one doesn't exist)
Add Fixes #<number> or Closes #<number> to this PR description

See CONTRIBUTING.md for details.

github-actions · 2026-01-11T08:20:07Z

The following comment was made by an LLM, it may be inaccurate:

No duplicate PRs found

rekram1-node · 2026-01-14T17:07:32Z


  const cost = createMemo(() => {
-    const total = messages().reduce((sum, x) => sum + (x.role === "assistant" ? x.cost : 0), 0)
+    const total = session().cost ?? 0


you would want to fallback to the messages cost right cause otherwise opening old sessions would show 0

It should be handled by the migration script for old sessions as well, but yeah it makes more sense to fallback to the old method instead of defaulting to zero. updated.

rekram1-node · 2026-01-14T17:08:04Z


+  export const getCost = fn(Identifier.schema("session"), async (id) => {
+    const read = await Storage.read<Info>(["session", Instance.project.id, id])
+    return read.cost ?? 0


prefer leaving as undefined so we can properly do checks in frontend right

makes sense, updated

this informs the caller function that cost can be undefined so it can properly handle it, instead of just defaulting to 0.

…cts style

…to 0

rekram1-node · 2026-01-15T16:50:25Z

+    async (dir) => {
+      log.info("migrating session costs")
+      const startTime = Date.now()
+      let migratedCount = 0
+
+      for await (const sessionPath of new Bun.Glob("session/*/*.json").scan({
+        cwd: dir,
+        absolute: true,
+      })) {


do we have to do a migration?

I think it's fine if only new things are updated, some people have a LOT of sessions

would be awesome to have a way to run the migration manually if its not automatic.

@rekram1-node with the fallback to deriving cost from messages present in the memory (from commit affc11a), migration is not strictly required in a sense that it will break the functionality but for older sessions the cost reporting will still be bugged.

from my local testing the migration was fine but again I don't know the extent of how many sessions people have, it could be a concern.

as @maharshi365 mentioned I can also add lazy migration, that only runs when a session is loaded, checks if the session has cost field, and run the migration if needed. I am currently not aware if users can manually run migrations in OC or not, also if it's fine from maintainers perspective to only updated new sessions I am fine with that as well, let me know @rekram1-node .

I think one time migration is probably way more important than whatever slowness there is in startup. Its not just stale data, but incorrect cost data that is being shown.

…culation

…t makes no difference to use existsSync

okay so fs.stat is used in the codebase instead of existsSync

bluet · 2026-02-05T23:14:28Z

Thanks for this fix! One consideration: addCost() only updates the current session, so subagent costs (via Task tool) won't roll up to parent sessions. For multi-agent workflows, the sidebar will still under-report.

Would you consider adding parent propagation via the existing parentID chain? Happy to discuss or contribute a follow-up PR.

Related: #11027 (subagent costs not aggregated)

I've also filed a comprehensive architecture proposal: #12377

IdrisGit · 2026-02-06T13:48:44Z

@bluet I am happy to discuss further on this, maybe we can have a proper tracking of the main agent cost and subagent cost for a proper breakdown, but first this PR needs to be merged or any improvement suggestions from the core team (cc: @thdxr)

IdrisGit · 2026-02-28T12:08:33Z

I have updated the PR to use the new SQLite db and have removed the old migration script, now this is forward fix PR (it will only work for new sessions only)

bluet · 2026-03-18T19:28:11Z

Hi @IdrisGit @rekram1-node @thdxr , just would like to know if this is still planned?

IdrisGit · 2026-03-19T02:06:43Z

@bluet I haven't recieved any feedback from the team, waiting on that.

wasd171 · 2026-04-21T20:15:24Z

Just got hit with x2 charge compared to what was visible in the UI :/
Would be great to get this PR merged!

Ale-SaP · 2026-05-08T18:18:28Z

Bumping this, shouldn't cost related issues be priority?

tailwhipstruggle · 2026-05-13T17:15:51Z

Looking forward to the merge resolution here. Much love

aravindparappil46 · 2026-06-04T23:00:15Z

Same here! Looking forward to this fix!

Ale-SaP · 2026-06-16T12:09:50Z

Looking forward to this! There seem to be merge conflicts, if this is not solved by next week I'll take a stab at it myself ;)

IdrisGit · 2026-06-20T17:53:36Z

I am going to close this PR now for a few reasons:

The issue associated with this PR was closed as not planned by the team. (Issue session-cost/spent-value under reported for sessions with 100+ messages #7767).
It has been sitting stale for a while now and codebase has changed alot, with the plugin system and refactor to EffectTS.
I am unavailable for the next week and can't work on the conflict resolution.

If someone wants to take up, please do, I might be able to help with testing next week if needed. I had already used sqlite so you can steal/copy that if you want.

Apologies to everyone who have been subscribed to this PR for the late resolution.

Integralist · 2026-07-17T15:22:16Z

👋🏻

Just in case someone is interested...

I've made a fork of opencode and added two really important features to it (file cycling + sub-agent costs), and then decided to add a few other things that improve the quality of life in opencode (see my changelog and links to the commits if you want them; or just use my fork):

https://github.com/Integralist/opencode/blob/custom-features/FORK.md

File Cycling in Permission Prompt: (e74ec3ad3)
Exposed Sub-agent Cost Calculations in TUI Sidebar: (a1f59f85e)
Added global /btw command (as a toggleable overlay): (b52d39fb3)
Fixed @ Autocomplete Resolution for External Paths: (8fcf878af)
Added Session Recap Card: (39a8902e6)
Fixed Copy-on-Select in Permission Prompt: (88cb2bb67)
Sorted Skills Dialog Alphabetically: (277fd693e)
Added /skills: Sub-completion: (e3db58627)
Added ctrl+r Prompt History Search: (14c3c6aaa) (/rename is still available for session renaming).

Screenshots

Notice the "1/3", you can use [ and ] to cycle through the edits to be sure you're happy with all of them:

Notice the sub-agent cost followed by the sub-total:

Notice the /btw overlay (you can also do things like /btw --model="gemini-3.1-pro-preview" --effort="high" here's my prompt!" if you need to override the sub-agent with a specific model and effort).

Here is what auto-complete looks like now that you can @../ out of the project directory:

This is the Claude Code "recap" feature I added:

So much nicer when Skills are sorted:

Yay! My /... menu is still clear of skills (like how opencode works currently, so I can focus looking through harness specific slash commands), whilst at the same time if I type a colon /skills: then it'll invoke a skill autocomplete without going to a separate overlay:

IdrisGit added 3 commits January 10, 2026 23:03

feat(opencode): add cost tracking to the session information

a863bc0

fix(tui): read actual cost from the session informatin instead of der…

ba86463

…iving from the messages array max 100 messages are kept in the store/memory which leads to misreporting of the actual spend value

feat: add migration step to populate old session with cost

9ca6a61

github-actions Bot added the needs:issue label Jan 11, 2026

fix: forked sessions should start with $0 spent value

97ee252

github-actions Bot removed the needs:issue label Jan 11, 2026

rekram1-node reviewed Jan 14, 2026

View reviewed changes

IdrisGit added 3 commits January 15, 2026 07:15

fix: return undefined instead of 0 if cost is not found

d6dbb1d

this informs the caller function that cost can be undefined so it can properly handle it, instead of just defaulting to 0.

chore: remove log I added for debugging as it doesn't match the proje…

96212fa

…cts style

feat: fallback to deriving cost from messages rather than defaulting …

affc11a

…to 0

IdrisGit requested a review from rekram1-node January 15, 2026 01:57

rekram1-node reviewed Jan 15, 2026

View reviewed changes

IdrisGit requested a review from rekram1-node January 19, 2026 07:47

rekram1-node and others added 5 commits January 25, 2026 11:32

Merge branch 'dev' into fix-session-cost-calculation

4bd7c4a

Merge remote-tracking branch 'upstream/dev' into fix-session-cost-cal…

066aca8

…culation

fix: use existsSync now that exists is also deprecated from Bun and i…

1797fc0

…t makes no difference to use existsSync

fix: use fs.stats instead

76a6f62

okay so fs.stat is used in the codebase instead of existsSync

Merge branch 'dev' into fix-session-cost-calculation

bad10d8

thdxr force-pushed the dev branch from cbab81f to 2d3c7a0 Compare January 30, 2026 04:50

opencode-agent Bot force-pushed the dev branch from 00637c0 to 71e0ba2 Compare January 30, 2026 14:32

thdxr force-pushed the dev branch 3 times, most recently from f1ae801 to 08fa7f7 Compare January 30, 2026 14:37

IdrisGit and others added 3 commits January 30, 2026 23:58

Merge branch 'dev' into fix-session-cost-calculation

238521c

Merge branch 'dev' into fix-session-cost-calculation

2975b2d

fix: commit types as I have added new cost key to the session

736f67e

IdrisGit force-pushed the fix-session-cost-calculation branch from b5e01b5 to 736f67e Compare January 31, 2026 14:54

This was referenced Feb 5, 2026

Cost of session doesn't include cost of subagents #11027

Closed

Multi Model Cost Calculations are Bugged #7387

Closed

[RFC] Cost Tracking Architecture: Subagent Aggregation + Multi-Model Correctness #12377

Closed

marius-kilocode mentioned this pull request Feb 25, 2026

TUI cost of session doesn't include cost of subagents Kilo-Org/kilocode#6321

Closed

IdrisGit and others added 3 commits February 28, 2026 16:40

Merge branch 'dev' into fix-session-cost-calculation

9afbfea

fix: remove migration as OC had now moved to sqlite

d7f0965

feat: update cost calculation to use sqlite and generated migration

1dc8fc5

stefanmatar mentioned this pull request Apr 10, 2026

Sidebar cost should include subagent session spend #21818

Closed

opencode-agent Bot force-pushed the dev branch from 2f2ed11 to 9f201d6 Compare April 16, 2026 21:55

matteo-pacini mentioned this pull request Jun 16, 2026

feat(opencode): sidebar whole-tree cost total + bespoke home caption matteo-pacini/nixos-configs#317

Merged

IdrisGit closed this Jun 20, 2026

github-actions Bot mentioned this pull request Jul 18, 2026

📊 AI CLI 工具社区动态日报 2026-07-19 litang9/big_model_radar#230

Open

AndyS77 mentioned this pull request Aug 20, 2026

fix(core): roll up subagent cost into parent session and fix fork double-counting #43645

Open

4 tasks

Uh oh!

Conversation

IdrisGit commented Jan 11, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

What does this PR do?

How did you verify your code works?

OpenCode v1.1.12

OpenCode local

Uh oh!

github-actions Bot commented Jan 11, 2026

Uh oh!

github-actions Bot commented Jan 11, 2026

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

bluet commented Feb 5, 2026

Uh oh!

IdrisGit commented Feb 6, 2026

Uh oh!

IdrisGit commented Feb 28, 2026

Uh oh!

bluet commented Mar 18, 2026

Uh oh!

IdrisGit commented Mar 19, 2026

Uh oh!

wasd171 commented Apr 21, 2026

Uh oh!

Ale-SaP commented May 8, 2026

Uh oh!

tailwhipstruggle commented May 13, 2026

Uh oh!

aravindparappil46 commented Jun 4, 2026

Uh oh!

Ale-SaP commented Jun 16, 2026

Uh oh!

IdrisGit commented Jun 20, 2026

Uh oh!

Integralist commented Jul 17, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Screenshots

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

9 participants

IdrisGit commented Jan 11, 2026 •

edited

Loading

Integralist commented Jul 17, 2026 •

edited

Loading