At a glance
- Did you know
- Agent-to-agent protocols let agents from different teams or vendors hand work to each other.
- Rule of thumb
- Treat another agent like an external API: timeouts, retries and a budget per call.
- Watch out
- Cascading delegation; remote quota; partial failure.
Its settings in ScaleMySystems
What you can change on it in the lab, and what each number does.
- Concurrency (slots)
- Calls it can work on at once (per instance when autoscaling). Needed slots ≈ calls per second × seconds each takes. Extra calls wait in the queue, then are rejected.
- Queue capacity
- Calls allowed to wait for a free slot. A bigger queue absorbs bursts but adds waiting time; 0 rejects straight away.
- vCPU
- CPU cores available. Needed ≈ calls per second × CPU per request ÷ 1000. Above about 90% busy it slows down and may crash.
- CPU per request (ms)
- CPU time each call burns. Part of what the component is; make the code cheaper to lower it.
- Latency (p50) (ms)
- Typical time one call takes here, before any calls it makes itself. Slots are held for this long.
- Latency (p99) (ms)
- The slowest 1% of calls. Callers must set their timeout above this or they cut off healthy calls.
- Timeout to dependencies (ms)
- How long it waits for each call it makes before giving up. Set it above the dependency’s p99 but low enough that a dead dependency does not hold every slot.
- Error rate
- Share of calls that fail on their own (bugs, declines, flaky tools). An agent that calls it on every step multiplies this.
- Quota (req/min)
- Calls allowed per minute (an API key or provider limit). Calls over it get 429s. Needed = calls per second × 60, with headroom.
Problems that start with it
- Partner agent goes offline Your travel agent books hotels through a partner’s agent over A2A. The partner is down from 15 s to 35 s.
- Partner agent at capacity A partner agent you delegate to over A2A handles 20 tasks at once, about 2.5 s each. You send it 12 a second.
- Travel agent: airline partner overloaded A travel agent books flights through an airline’s agent over A2A, which handles 15 tasks at once.
- Retries at every hop of an agent chain A concierge agent calls a booking agent, which calls an airline’s agent over A2A (40 slots, about 4 s a request). Both callers time out after 8 s and retry twice at once. At 15 s bookings jump 2.5× for 10 seconds.
Full lesson coming soon
Lessons are being added one component at a time: how it works, its settings, a live exercise to break and fix it, interview questions and a short check. See the Circuit breaker lesson for what one looks like.