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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, and the description adds substantial context beyond those: owner-scoping, plan/auth requirements, newest-first ordering, 'light rows' for the timeline, team-only events, and the fact that sessions are created in the web app. No contradiction with annotations.

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?

Although the description is long, it is densely informative and each clause earns its place. The two-mode structure is front-loaded琳琅 and the read-only/auth note is quick, so an agent can parse the essential behavior without wading through fluff.

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 two modes, a team-event condition, plan restrictions, and relationships to several sibling tools, the description covers everything needed to select and invoke it correctly. The output schema exists to cover return values, so no explanation of those 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?

The schema already describes session_id fully, including the 'Session not found.' behavior for non-owned ids, so the baseline is 3. The description adds value by explaining what session_id actually yields (run timeline light rows, team events) and how to get full results via me.validation_history, pushing it slightly above baseline.

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 opens with a specific verb+resource pair: 'list or inspect the authenticated user's Governed Sessions'. It distinguishes two modes (no args lists all; session_id inspects one) and states the session's key characteristics, making it unmistakably different from sibling listing/inspection tools.

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 explicitly explains when to use each mode, names the complementary tool for fetching full run results (me.validation_history), and tells the user how to attach new runs via architect.validate, design.validate, and spec.validate. This is clear routing guidance, not just a description.

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