Read original native session history

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

Annotations already cover readOnly/idempotent/no-destruction, but the description adds real behavioral depth beyond them: backwards cursor pins the throughSeq cut, page stability across new events, restart survival, and an explicit 512 KiB error ceiling with a remediation hint. The only gap is that it doesn't describe the shape of the returned records.

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?

Five dense sentences with the core return/pagination behavior front-loaded and no filler. Some internal jargon ('throughSeq', 'Relay') assumes prior knowledge but does not waste space.

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 read-only, no-output-schema tool, the description covers return ordering, cursor mechanics, pagination stability, and the failure mode — enough for correct invocation. It stops short of explaining the sessionId parameter or record fields.

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 carries the whole burden. It explains cursor semantics (backwards, pins throughSeq) and refers to maxMessages (reduce on overflow), partially compensating, but ignores sessionId entirely and never states maxMessages' default of 25 or cap of 50.

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 (Return) and resource (complete native event records in native order) and scopes it to 'registered Harness workspace sessions.' However, it never names or contrasts the obvious siblings it competes with — search_session_history and read_session_context — so an agent must infer the distinction between reading full history vs. searching or reading 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?

There is no explicit when-to-use guidance. The reader must infer that this is for full sequential reading while search_session_history is for searching, and read_session_context is for context. No alternatives, exclusions, or triggering conditions are named.

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