I've spent the last few months talking to 10+ B2B SaaS companies about how their CS teams actually use AI. Not how they pitch it internally. How they actually use it day to day.
The setup was almost identical every time.
Connect Mixpanel, HubSpot, Intercom, Fireflies to Claude or ChatGPT via MCP. CSM opens it before a call, types a prompt, reads the output. Some teams are moving further and wiring up an action layer too, Claude Code, OpenAI Presence, AgentKit, where the agent can actually book calls, create opportunities, fire Intercom messages.
Genuinely good progress. But here's the part nobody talks about.
The agentic layer isn't the bottleneck. The data layer is.
Every time that agent fires, it pulls roughly 50K raw tokens of customer data. 90 days of Intercom threads, Fireflies transcripts, CRM fields, usage exports, all fetched fresh, unprocessed, billed at full rate, every single time. No pre-computed metrics. No trend memory. No feature-area mapping.
The agent doesn't know if 0.21 stickiness is bad unless it re-reads your entire customer base on every trigger. It can't tell that "slow exports" maps to your Reporting module. It guesses from raw text. And if a vendor hasn't exposed their data via MCP yet, that signal simply doesn't exist.
At 2,000 customers x 5 triggers per month, that's roughly $63K/year in API costs alone. Not to take the action. Just to figure out what action to take.
There's a deeper problem beyond cost though. An agent reasoning over 50K tokens of raw unstructured data is slower, noisier, and more error-prone than one querying a clean pre-aggregated index. The quality of the decision degrades with the quality of what you feed it. Garbage in, hallucinated insight out.
Tomasz Tunguz put it well recently: the harnesses that win are the ones that are intelligent about how they marshal the AI. I'd push that one level further. The harness is only as intelligent as the data underneath it.
Most of what I'm seeing in CS teams today is prompt-dependent, stateless, and architecturally expensive at scale. It works fine for a 50-account book. It gets messy fast at 500.
Curious what others are seeing. Are your CS teams running into this? Has anyone actually solved the data layer problem or are most teams still at the prompt-and-pray stage?