session_events

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

With no annotations present, the description carries the full transparency burden and does it well: it discloses consumption semantics ('delivered exactly once across calls'), ordering ('oldest first'), a non-consuming peek mode, and an important security property that payloads are untrusted. This goes well beyond basic descriptions.

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 compact, front-loaded with the core purpose, and every sentence adds value: read behavior, delivery semantics, security warning, and peek guidance. There is no filler or redundancy.

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 relatively simple read tool with no output schema, the description covers purpose, behavior, ordering, consumption, non-consuming access, and security considerations. It is sufficiently complete for an agent to select and invoke the tool correctly in most scenarios.

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?

The input schema already provides complete descriptions for all three parameters (100% coverage). The description reinforces the peek behavior and broadcast scoping but does not add substantial new semantic detail beyond what the schema already states, so the baseline score of 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?

The description clearly states the tool reads events addressed to the current session, including direct and broadcast events, with specific delivery semantics (oldest first, exactly once). This distinguishes it from sibling tools like session_send or session_wait, which write or wait rather than read.

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 clear operational guidance, especially the peek:true option to read without consuming and the security warning about untrusted payloads. It does not explicitly name alternatives or state when not to use the tool, so it falls just short of full differentiation.

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