2026-08-17-hermes-agent-the-per-subagent-tool-call-budget-jumps-50-to-250-and-a-migration

The per-subagent tool-call budget jumps 50 to 250, and a migration rewrites your config to match.

delegation.max_iterations default goes 50 -> 250 (_config_version 35 -> 36), with DEFAULT_MAX_ITERATIONS in delegate_tool.py kept in sync. The reasoning: leaf agents spend ~15-20 turns on reconnaissance before producing output, then ran out of budget mid-task and returned 'completed but unfinished' summaries (exit_reason=max_iterations while status=completed). The load-bearing part is _migrate_to_36, which on update lifts any config pinned at exactly the old default 50 to 250 -- because config values, once written, are not overwritten by default changes, so every existing install would otherwise sit at 50 forever. Deliberate overrides at any other value are preserved; an unset key inherits 250 at read time. The PR states its own risk: the cap is per child and children run concurrently, so this raises worst-case fan-out cost, with delegation.child_timeout_seconds (default 0 = off) as the only wall-clock backstop.

Channel: tagged-release. Ancestry: merge_commit_sha 50d98fc1f3d49d7a7b522eaa7f4553cd864a0218; compare/50d98fc1...v2026.8.16 -> status=ahead, ahead_by=743, behind_by=0 (ancestor of stable tag v2026.8.16).

Operator consequence: This is a spend change disguised as a default change, and it will apply to you on hermes update unless your config holds a non-50 value. If you deliberately inherited 50, write an explicit number down before upgrading -- the migration cannot tell an inherited default from a considered one. Combined with the concurrency raise, worst-case per-batch tool calls go from 150 to 2,500.

Receipt

• https://github.com/NousResearch/hermes-agent/pull/86506