chat_history_read

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

Beyond the readOnlyHint annotation, it adds valuable context: returns the resolved file path plus matching entries (newest last), describes path resolution with back-compat, warns that rotation invalidates refs, and notes that history entries are large so 'index' mode is helpful. These details give the agent a clear behavioral model.

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 concise at four sentences, each serving a distinct purpose: what it reads, when to use it, return shape, and filter guidance. No redundant text or filler.

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 tool with 8 optional parameters and no output schema, the description covers the core aspects: purpose, file location, filtering hints, and return format. It lacks explicit mention of error conditions or edge cases, but the schema and rich parameter descriptions fill the gap reasonably.

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 coverage is 100%, so the baseline is 3. The description adds a useful tip about combining 'session', 'last', and 'entry_type' filters, but it doesn't further explain each parameter or add semantics beyond what the schema already provides.

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 uses the specific verb 'Read' with a concrete resource ('chat-history JSONL') and gives exact paths, making the tool's function unambiguous. It differentiates from sibling 'chat_history_append' by emphasizing read-only access and mentions return contents (entries, resolved path).

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?

It clearly states the intended use case: recovering context from earlier sessions at the start of a new task. It also advises combining filters to narrow results, but it doesn't explicitly mention when not to use it or name alternative tools (e.g., memory_get) for different context sources.

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