Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, and destructiveHint=false, so the safety profile is covered structurally. The description adds meaningful context — the result is private, runs in a sandbox, and is pinned to a commit — but being truncated it never discloses cost, provisioning time, ownership, or what happens on repeat calls with the same name.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The opening is well front-loaded with the verb and resource, but the single sentence is truncated and the remainder is lost. Nothing is padded, but the definition as delivered is incomplete rather than tight.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

A mutating, open-world tool with three undocumented required parameters and no output schema needs far more from the description. It never states what is returned (a cell id? a URL?), how hosting is billed or scoped, or how to undo/stop it.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0% across three required parameters, so the description carries the full burden. It partially explains repo and commit (public repo, pinned commit) but says nothing about 'name' — whether it is a unique cell identifier, a display label, or what happens on collision.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific verb pair ('Build and host') and a specific resource ('private cell') plus the source ('public GitHub repo at a commit'), which is far more than a restatement of the name. It does not, however, explicitly distinguish itself from close siblings like host_cell or cell_publish, and the sentence is cut off mid-thought.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no guidance on when to use this versus host_cell, cell_publish, private_create, or host_stop. The phrase 'from a public GitHub repo at a commit' implies a precondition (public repo, pinned commit) but not a usage rule or alternative.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.