run_build

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

Annotations only mark it as a non-read-only, non-destructive operation; the description goes further by disclosing that output streams live to server logs, that an environment variable gates web-component apps, and that failures carry a plain-language hint. It omits whether the call blocks until completion or how long a build typically takes, but the added behavioral context is substantive.

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?

Three tight clauses with no filler, front-loaded with the action before the prerequisites. Slightly dense and could be split for readability, but nothing is wasted.

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?

With no output schema and no annotations beyond safety flags, the description covers what runs, the prerequisite chain, the conditional env var, and output visibility via live log streaming plus error hints. What is missing is how results/artifacts are retrieved after the build completes.

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 description coverage is 100%, so both repo and appName are already fully documented in the schema, including the list_repos/list_apps discovery pointers. The description adds no parameter-level detail (the ENV var mentioned is not a parameter), so the baseline 3 applies.

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?

States a specific verb and resource ('Run grunt-vb-build for a VBCS app'), so the agent knows exactly what operation executes rather than a generic 'build'. It does not distinguish itself from the sibling vbstudio_trigger_build or explain how the two build paths differ, leaving the sibling boundary to inference.

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?

Gives an explicit prerequisite ('Needs setup_build_tools first') and a conditional requirement ('VB_BUILD_COMPONENT_EXCHANGE_URL for apps using web components'), which is real when-to-use guidance. It stops short of stating when to prefer this over vbstudio_trigger_build or how it relates to vbstudio_build_status.

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