pio_build

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

No annotations are provided, so the description carries the full behavioral burden, and it delivers: it discloses the exact return structure (status, parsed errors with file/line/column, RAM/Flash percentages, last 40 lines, log path) and the potentially slow first build due to toolchain downloads. It implicitly signals a write/compile operation by naming 'pio run', which is well understood.

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?

Well-organized and front-loaded: core action first, then return-value summary, then workflow, then the latency caveat. Every sentence earns its place with concrete detail, though the output enumeration is somewhat long.

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?

An output schema exists, so return values are partially structured, and the description adds real enrichment on top: parsed error format, resource usage percentages, log path, and the first-build latency. The only notable gap is the complete absence of parameter semantics, which matters for a 4-parameter tool.

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 0%, so the description must compensate, yet it explains none of the four parameters (env, jobs, verbose, project_dir). Verbose and project_dir are somewhat inferable, but 'env' is semantically important in PlatformIO (selects build environment) and is left unexplained.

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 ('Compile') and resource ('the project'), explicitly maps to the underlying command (`pio run`), and the build action is clearly distinct from siblings like pio_run_target, pio_clean, and pio_upload. An agent can immediately tell what this tool does.

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?

The description conveys the iterative workflow ('Fix the listed errors, then build again') and the latency caveat, giving some guidance on how to use the tool in a loop. However, it never states when to prefer this over siblings such as pio_run_target or pio_check, and gives no explicit exclusions or alternative-routing conditions.

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