nexo_session_diary_write

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

No annotations are provided, so the description carries the full burden of disclosing behavioral traits. The description only states 'Write', implying mutation, but it does not clarify whether the operation is idempotent, destructive, or what happens on repeated calls. It also fails to mention any permissions requirements or side effects (e.g., does it auto-flush? trigger lifecycle events?). This lack of detail leaves the agent unaware of important behavioral constraints.

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 of 12 words, extremely concise. It front-loads the core action ('Write end-of-session diary') and immediately follows with the key content categories ('decisions, discards, and context for next session'). Every word earns its place, with no filler or repetition.

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?

Given the tool's complexity (12 parameters, no output schema, no annotations), the description is minimally adequate. It provides the high-level purpose and content categories, and the schema covers parameter details. However, it lacks information about the return value, error scenarios, and how this tool fits into the broader session lifecycle (e.g., is it called automatically? what triggers it?). This leaves gaps for an agent to navigate correctly.

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% for all 12 parameters, with thorough descriptions that explain the meaning and expected format (e.g., 'What was decided and why (JSON array or structured text)'). The tool's description adds no additional parameter information beyond what the schema already provides. According to guidelines, with high coverage the baseline is 3, and the description does not exceed it.

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 tool's purpose: 'Write end-of-session diary with decisions, discards, and context for next session'. It specifies the verb (write), the resource (diary), and the scope (end-of-session). It also differentiates from sibling tools like nexo_session_diary_read and nexo_lifecycle_write_fallback_diary by focusing on the structured content of decisions, discards, and context.

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 explicitly indicates when to use the tool: 'end-of-session diary', providing clear temporal context. However, it does not mention when not to use it (e.g., for mid-session logging) or suggest alternatives like nexo_diary_archive_write or nexo_continuity_snapshot_write, which could serve related purposes. This omission prevents it from achieving a perfect score.

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