Pick LangSmith if
engineers who already write agent code and will open traces when a run surprises them.
Read the LangSmith pageLangSmith vs PromptLayer
Our take
Pick LangSmith if engineers who already write agent code and will open traces when a run surprises them. Pick PromptLayer if aI teams who will pay Pro or Team so more than 10 playground runs a day and 2.5k requests sit on a shared registry.
LangSmith
LangChain’s hosted observability and eval
Best for
LangSmith See what an agent did, then score it
PromptLayer Ship prompts without a redeploy
Free plan
LangSmith $0 · / seat / month. 1 seat. 5,000 base traces/month, then pay-as-you-go. 7 LSU Fleet allowance/month. Community support
PromptLayer $0 · /month. 5 users; 2.5k requests / month; 1 workspace; 250 eval cell executions / month; 10 playground runs / day; 10MB max dataset; 750 agent node executions / month. SaaS
Lowest paid
LangSmith Plus $39/mo
PromptLayer Pro $49/mo
Coding agent
LangSmith
PromptLayer Agents / workflows
Runs where
LangSmith Hosted
PromptLayer
Watch out
LangSmith Traces after 5k / 10k bill in arrears
PromptLayer Free is 2.5k requests and 10 playground runs a day
Last checked
LangSmith 2026-10-22 · langchain.com/pricing
PromptLayer 2026-10-22 · promptlayer.com/pricing
Which one, then?
Pick PromptLayer if
aI teams who will pay Pro or Team so more than 10 playground runs a day and 2.5k requests sit on a shared registry.
Read the PromptLayer page