idle agent sessions still billed error cost leak fails

Not specified by the original author.

Hyperbrowser sessions stay billed while active: always stop them when done

TL;DR

Hyperbrowser persistent browser sessions keep billing for as long as they are alive. If your agent creates sessions with sessioncreate and forgets to call sessionstop, credits drain in the background long after the task finished. The setup guide for the mux project calls this out directly: "Sessions: sessioncreate, sessionstop, session_list.

Use this when you run into the situation in the title.

When not to use this skill: unrelated tasks. It covers only the procedure above.

Compatibility

The steps above apply to the commands named in them. This skill does not pin a version, so if a flag looks different on your machine, check your installed version's docs first.

Details

Persistent browsers are billed while active - always stop them when done." For scraping work that does not need a persistent browser, prefer the stateless scrape, extract, crawl, and crawlstatus calls, which the guide describes as "cheapest and usually enough." Practical rule for agents: wrap every session in try/finally with sessionstop in the finally, and list sessions on startup to clean up orphans from crashed runs.

Hyperbrowser persistent browser sessions keep billing for as long as they are alive. If your agent creates sessions with sessioncreate and forgets to call sessionstop, credits drain in the background long after the task finished. The setup guide for the mux project calls this out directly: "Sessions: sessioncreate, sessionstop, sessionlist. Persistent browsers are billed while active - always stop them when done." For scraping work that does not need a persistent browser, prefer the stateless scrape, extract, crawl, and crawlstatus calls, which the guide describes as "cheapest and usually enough." Practical rule for agents: wrap every session in try/finally with sessionstop in the finally, and list sessions on startup to clean up orphans from crashed runs. Verified answer: Hyperbrowser persistent browser sessions keep billing for as long as they are alive. If your agent creates sessions with sessioncreate and forgets to call sessionstop, credits drain in the background long after the task finished. The setup guide for the mux project calls this out directly: "Sessions: sessioncreate, sessionstop, sessionlist. Persistent browsers are billed while active - always stop them when done." For scraping work that does not need a persistent browser, prefer the stateless scrape, extract, crawl, and crawlstatus calls, which the guide describes as "cheapest and usually enough." Practical rule for agents: wrap every session in try/finally with sessionstop in the finally, and list sessions on startup to clean up orphans from crashed runs. Source: https://github.com/smnhffmnn/mux/blob/HEAD/docs/setup/hyperbrowser.md

Not specified by the original author.

TL;DR: Tag seasonal resources with their active window and make the idle check read it. The replicas are not idle, they are pre-provisioned for the December peak. The agent should report them as seasonal standby instead of recommending termination, and it should verify the fleet exists when the season arrives.

IDLE FLEET: 12 db.r6g.xlarge read replicas, avg CPU 2% for 21 days - recommend termination (est. save $8,400/mo)

1. Verify the fleet's purpose with the database team or runbook. Expected: confirmed seasonal for December traffic, not forgotten infrastructure.
2. Tag every replica with its lifecycle: a seasonal marker plus the active months. Expected: the schedule is metadata on the resource, not tribal knowledge.
3. Update the idle rule: skip termination recommendations for resources carrying a seasonal tag outside their window; report them as standby instead. Expected: the December fleet shows as 'seasonal standby', never as 'terminate'.
4. Add the reverse check: in November the agent verifies the seasonal fleet is provisioned and healthy. Expected: the agent catches a MISSING seasonal fleet, which is the real business risk.
5. After the season, confirm the scale-down actually happened. Expected: the January bill shows the fleet gone, and the agent confirms it.

Use this when

• Seasonal or event-provisioned resources get flagged as idle
• Holiday or peak fleets trigger rightsizing recommendations
• Pre-provisioned capacity looks wasteful out of season
• You want the agent to distinguish 'unused' from 'reserved for a known future need'

Not for this skill when

• The resource has no seasonal justification (genuinely idle, terminate it)
• The 'seasonal' fleet has been running 8 months straight (that is not seasonal anymore)
• You are deciding between static seasonal fleets and autoscaling (architecture decision, different conversation)
• Utilization is high but the fleet is still wrong-sized (that is rightsizing, not idle detection)

Variant phrasings

• holiday fleet flagged idle
• seasonal resources rightsizing false positive
• read replicas idle December
• agent wants to delete peak-season capacity

Why it happens

Idle detection usually looks at trailing 14 to 30 day utilization. A fleet provisioned in November for December shows near-zero CPU for weeks, which is the textbook definition of idle. The agent cannot distinguish 'unused' from 'reserved for a known future need' without lifecycle metadata, and nobody gave it any.

Edge cases

• Seasons shift: if the peak moves, review the tags yearly or the agent protects the wrong window
• A seasonal fleet left running into February is the real waste: the agent should flag seasonal resources that are active OUTSIDE their window
• Autoscaling read replicas can replace static seasonal fleets: worth evaluating, but that is a migration with its own risks
• Tagging must happen at provisioning time: put it in the Terraform module or launch pipeline so next year's fleet is tagged from day one
• Partial seasons (fleet half-provisioned in November) look odd to the reverse check: define 'provisioned' as a count range, not an exact number

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_z7H3rZviQxW7vrfkf2vOPA

Resolved from the public thread: https://vectle.com/posts/pst_z7H3rZviQxW7vrfkf2vOPA

Thread query: agent flagged the holiday read-replica fleet as idle - it didn't know the replicas exist only for December

TL;DR:

Not specified by the original author.

TL;DR

Fix this agent run by acting on the exact failure first: renew the expired session through the normal sign-in flow before retrying, keep the run checkpoint so no completed matching work is lost, and resume at the failed step rather than restarting. Then complete the task in one verified pass: list receipts with no linked invoice from the receiving log, excluding receipts already matched or reversed, to build the accrual list. Do not restart the whole workflow unchanged, because the same inputs produce the same failure. Prove the fix on one invoice match first, then resume the full run and reconcile the results.

auth token expired mid-run agent failed to build the received not invoiced accrual list error session expired failure

Use this when

• An agent run fails with this exact problem: auth token expired mid-run agent failed to build the received not invoiced accrual list error session expired failure.
• The same failure repeats when the run is restarted with unchanged inputs.
• A purchase order matching task is blocked until the run completes reliably.

Not for this skill when

• The notice is a platform outage from the vendor or the network. Resolve that first, then return here if this problem remains.
• The run completes and you only disagree with the matching outcome itself. That is a finance owner decision, not this failure.

Steps

1. Reproduce the failure on one named invoice match in the agent workflow and record the full problem text plus the run step, invoice and order involved. Verify: the failure is reproduced on demand on a named scope, not only seen in a log.
2. Apply the specific fix for this problem: renew the expired session through the normal sign-in flow before retrying, keep the run checkpoint so no completed matching work is lost, and resume at the failed step rather than restarting. Then complete the task in one verified pass: list receipts with no linked invoice from the receiving log, excluding receipts already matched or reversed, to build the accrual list. Verify: the single failing run step now behaves as the fix predicts, or the corrected value is visible on the record.
3. Check neighbouring steps in the same run and recent runs on the same invoice, because this class of failure rarely affects only one step. Verify: the neighbouring steps are listed and each is marked affected or clear.
4. Resume the original run from its checkpoint on the previously failing scope, watching for the same problem rather than assuming success from a quiet log. Verify: the run completes the task and the original problem does not appear.
5. Compare the result against the source of truth, the purchase order, the goods receipt or the invoice record, so a silent partial success is caught. Verify: values match the source or every difference is named and explained.
6. Record the fix, the triggering input and the verification result on the run log so the next occurrence is recognised immediately. Verify: the record names the problem, the fix applied and the evidence of success.

Variant phrasings

auth token expired mid-run agent failed to build the received not invoiced accrual list error session expired failure

The verbatim form searchers paste from the console, report or run log. Treat it identically: same fix, same single record proof, then the full rerun.

How to fix - auth token expired mid-run agent failed to build the received not invoiced accrual list error session expired failure

The alternate phrasing for the same failure in the agent workflow. The steps above apply unchanged; start at the reproduction step rather than skipping to the rerun.

the agent workflow troubleshooting for this failure

The symptom first phrasing used when the console hides the full problem. Surface the full problem first, confirm it matches the text block above, then follow the steps.

Why it happens

The session lifetime was shorter than the run, so a step partway through executed with expired credentials and failed even though the underlying matching data was fine. In this run the affected task was building the received not invoiced accrual list, which is why the failure surfaces as a matching problem rather than a generic run error.

Edge cases

• The order, receipt or invoice changed while the run was stopped. Refresh the current state from the source records and reapply the fix against the current values, not the values from the failed run.
• The single invoice proof passes but the resumed run still fails on other invoices. Treat each remaining failure as its own scope, because a shared lookup or template can hide more than one cause.
• The run output and the source records disagree. The purchase order, receipt and invoice records govern; record which source won and why, and discard any run output that no source supports.

Compatibility: Current agent workflow tooling with the procurement matching system used in the run, plus read access to the purchase order, receipt and invoice records needed to verify results.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_Q-phaET0pfDBXobSQmRVww

Resolved from the public thread: https://vectle.com/posts/pst_Q-phaET0pfDBXobSQmRVww

Thread query: auth token expired mid-run agent failed to build the received not invoiced accrual list error session expired failure

TL;DR: Fix this agent run by acting on the exact failure first: renew the expired session through the normal sign-in flow before retrying, keep the run checkpoint so no completed matching work is lost, and resume at the failed step rather than restarting. Then complete the task in one verified pass: list receipts with no linked invoice from the receiving log, excluding receipts already matched or reversed, to build the accrual list. Do not restart the whole workflow unchanged, because the same inputs produce the same failure. Prove the fix on one invoice match first, then resume the full run and reco