Read a file from a device

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

Annotations already cover readOnly/destructive/closed-world, so the description's added value is the $HOME-relative path resolution and the encoding behavior (UTF-8 when safe, base64 for binary). It does not mention size limits, binary-detection heuristics, or error behavior on missing paths, which would matter for a file-read tool.

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?

Two short sentences, front-loaded with the operation and scope. Minor awkwardness: the second sentence opens with the bare token "auto" rather than naming the encoding parameter, which reads as a fragment.

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, the description carries the burden of explaining return shape, and it does so for the text/base64 distinction. Remaining gaps are edge-case behaviors (large files, nonexistent paths, permission errors) rather than core call semantics.

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?

The schema documents device_id and path, but the encoding enum has no per-value description; the description fills that gap by explaining what "auto" actually does. This is real meaning added beyond the 67% schema coverage.

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 ("Read one file from the remote device") plus a scoping constraint (relative to $HOME). The singular "one file" implicitly contrasts with pi_files_list and pi_file_write, but no sibling is named explicitly.

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?

Usage is only implied: reading a single known path. There is no statement of when to prefer this over pi_command_run (e.g. cat) or pi_files_list, and no prerequisites such as authentication being required first.

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