opencode_sessions

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only says 'List', which implicitly suggests a read-only operation, but it does not state that explicitly, nor does it mention any side effects, authorization requirements, rate limits, or output format details. For a listing tool this is a minor gap, but the description fails to disclose even basic safety or scope constraints beyond the directory parameter.

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 description is a single sentence that is concise and front-loads the core action ('List OpenCode sessions for a directory'). The purpose hint is added in parentheses without verbosity. There is zero wasted content and the structure makes the tool's intent immediately clear.

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?

For a simple list tool with only one parameter, the description conveys the essential information. However, since there are no annotations and schema descriptions are absent, it would benefit from mentioning prerequisites (e.g., OpenCode must be installed or the directory must exist) or clarifying the output structure. The presence of an output schema mitigates the need to explain return values, but behavioral details remain sparse.

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 description coverage is 0%, so the description must compensate for the undocumented 'directory' parameter. It does add meaning by explaining that the directory scopes the session listing, which is helpful. However, it does not specify the expected format (path, existence requirements, or any constraints) and offers no example. It partially compensates for the schema gap but not fully.

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 clearly states the action ('List') and the resource ('OpenCode sessions') with a scoping qualifier ('for a directory'). It also adds a purpose hint ('to pick a session_id to reuse'), which clarifies why an agent would call it. It is distinct from the sibling tool names (run, answer, etc.) without confusion, though it does not name any sibling explicitly, so it loses a point for not explicitly differentiating.

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 implies usage: it is meant to help pick a session_id for reuse, which suggests it is called before tools like opencode_run or opencode_answer. However, it does not explicitly state when to use this tool versus alternatives, nor does it mention any conditions or exclusions. The guidance is implied rather than explicit, which is adequate but not strong.

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