Read a Pi session

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds real value beyond that by disclosing that pages are stable and revision-bound (a consistent snapshot), which tells the agent reads won't shift under concurrent edits. It stops short of describing error or truncation behavior.

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 sentences, zero filler, with the core read/pagination behavior front-loaded and the mode nuance second. Every clause carries information.

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 an output schema present, return values need not be described, and pagination plus mode are both covered. Minor gaps remain: what 'the active branch' means in this domain and ordering guarantees, but nothing essential for invoking the tool correctly is missing.

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%, with each parameter documented in the schema including the mode enum and cursor semantics. The description's mention of default vs raw mode restates what the schema already explains, adding no syntax or format detail beyond it. Baseline 3 is appropriate.

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 ('Read') and resource ('the active branch'), and clarifies that it returns stable, revision-bound pages rather than arbitrary data. It distinguishes itself functionally from siblings like pi_session_search/pi_session_find, but never names them, so the differentiation is implicit rather than explicit.

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 gives a default-versus-raw distinction ('Defaults to visible conversation content; raw mode includes metadata and tool internals'), which is a usage cue. However, it offers no guidance on when to prefer this tool over pi_session_context, pi_session_search, or pi_session_find, leaving sibling selection to inference.

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