Writing
Page 5 of 5
Older posts on measuring MCP servers — retries, empty results, schema cost, and what the four outcomes of a tool call actually tell you.
Page 5 of 5
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Engineering 4 minSessions cross midnight, and other counter traps
Bucketed counters are how a dashboard stays fast. But some things are not buckets, and summing them by day quietly double-counts every one that spans two.
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Measurement 4 minWhat a 10kb tool response actually costs
Roughly 2,500 tokens, about a cent, and a chunk of the context window that the rest of the conversation no longer has. The last one is the expensive part.
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Tool design 5 minWriting tool descriptions for a reader who gets one pass
The model reads your description once, alongside forty others, and decides immediately. Everything that makes documentation good makes a tool description worse.
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Engineering 4 minWhat gets computed at 2am, and why it cannot be done sooner
Three of the sixteen metrics need to see what came after a call. That is not knowable when the call arrives, so it happens overnight — and the dashboard says so.
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Engineering 5 minCounters exist so that calls can be deleted
Every call is written twice — once as a row you will throw away, once as a counter you keep forever. The second one is what makes the first one disposable.
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Tool design 4 minNaming tools for a reader who cannot see your API
The model has your tool name, your description, and nothing else. No source, no docs site, no colleague to ask. The name is doing more work than you think.
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Engineering 5 minInstrumentation must never break the thing it measures
The SDK runs inside someone else's production server. Three rules follow from that, and none of them are negotiable — including handing the server back unmodified.
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Measurement 4 minWhich tools get called together, and what that tells you
Models chain tools. When two of yours are always called in sequence, that pattern is usually a design note you have not read yet.
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Measurement 4 minCost per session is the number to quote
Not the monthly bill — that measures how popular you are. Cost per session measures how expensive you are, which is the part you control.
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Privacy 4 minFive questions a security review asks about your analytics
If your MCP server touches customer data, someone will ask what your monitoring vendor receives. These are the five questions, and the answers that end them.