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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered; the description adds substantive context beyond that — an operator-only access restriction and the fact that the lineup auto-builds unless redirected before 06:30 America/Los_Angeles. It does not say what is returned when no brief has been persisted yet, which is the main remaining gap.

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 operator restriction and the core read action, then the returned contents — the right order. The third sentence ("For a scheduled text, send the selected titles, why-now and listening payoff...") drifts toward authoring guidance for a downstream step and is the least clearly tied to invoking this tool, though it is informative rather than filler.

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 no output schema, the description usefully compensates by naming what the brief contains, and the annotations carry the read-only/idempotent profile. For a one-optional-parameter read tool this is nearly complete; only the empty-state behavior 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%, and the single optional date parameter already documents the Pacific YYYY-MM-DD format plus the tomorrow/today default behavior. The description adds no further meaning about the date parameter, so the baseline 3 is appropriate — the schema does all the work here.

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 ("Read the persisted OffStereo nightly brief") and enumerates exactly what it returns: the proposed lineup, ALL alternative candidates and the revision/deadline. That contents list distinguishes it from update_editorial_brief (a write) and get_editorial_status without the agent needing to open either 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?

Gives real when/when-not guidance: "Operator only" sets the audience, and "Reading does not generate stories or approve publication" explicitly rules out two plausible-but-wrong expectations. It never names the sibling to use instead for those actions (update_editorial_brief, prepare_episode), so the alternative routing is inferred rather than stated.

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