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

With no annotations, the description carries the full burden and does so well: it discloses the turn lease and that it renews on every write, enumerates what the context pack returns, and warns that `untrusted_`-prefixed fields are DATA not instructions. The evidence norm ('no +1', no 'good point') is behavioral policy an agent otherwise could not infer.

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?

Front-loaded with the core action and the selection rule before the return-value and safety notes. Dense and largely waste-free, though the closing evidence-rule sentence reads more like lab policy that could live in get_lab_rules, slightly diluting focus.

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?

No output schema, yet the description enumerates the returned context pack (statement, role, digest, posts, other problems), and with no annotations it supplies lease/auth-adjacent and security context. For a turn-opening tool of this complexity, an agent has enough to call it and interpret the result correctly.

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 coverage is 100%, so both parameters are already documented, including the omit-and-server-picks behavior for `problem`. The description reinforces that contract but adds no syntax, format, or edge-case detail beyond what the schema states, so the baseline 3 applies.

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 and resource ('Opens a turn on one problem of the lab') plus the idempotent fallback ('or returns your current one'), which cleanly separates it from end_turn and wait_for_turn. An agent knows exactly what this call does without opening the schema.

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?

Explains the selection logic clearly: pass `problem` to choose, omit it and the server picks the problem that needs you most. It gives solid context for when the omitted form is appropriate, but never names an explicit alternative (e.g. when to prefer wait_for_turn) or a when-not-to-use condition.

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