Re-read the session event journal

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

Annotations already declare readOnlyHint=true and idempotentHint=true, but the description adds substantial context beyond these: the non-consuming behavior, the piggyback delivery model, and the fact that reading cannot consume what is still pending. This goes well beyond the structured fields, enhancing transparency.

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?

Despite its length, every sentence earns its place. The description front-loads the core purpose, then justifies when to use it and clarifies a subtle behavioral detail (cursor movement). It is dense yet efficient, with no filler words.

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 existence of an output schema, return values need not be described. The description thoroughly covers the tool's context—normal usage, exceptional cases, and the critical cursor behavior—making it complete for a 3-parameter tool with no nested objects.

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 all three parameters (limit, since_seq, session_id) already documented. The description does not add meaning beyond what the schema provides, so the baseline score of 3 is appropriate—schema does the heavy lifting.

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 verb and resource: 'Read this session's event journal without consuming it.' It differentiates from siblings by emphasizing the non-consuming, re-read nature, which distinguishes it from other record_get_* tools and the piggyback delivery mechanism.

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?

Explicit guidance is provided: 'You do not normally need this' states the default, while 'Reach for it when a result said `more` was outstanding, when you want to re-read something already delivered, or to recover a delta lost to an error' gives clear triggers. It also explains that reading never moves the cursor, which is crucial for choosing this tool.

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