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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so safety is covered. The description adds genuinely non-structured behavior: the detection thresholds that define each signal, and the truncation contract ('first 5 entries of each list, with truncated saying how many were left out'), which an agent must know to avoid mistaking a short list for an empty one.

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?

Two sentences, front-loaded with the definition of what signals are returned, followed by output-shape behavior. The second sentence largely duplicates the response_format schema text, which is mild waste, but the dense threshold clauses all carry information an agent would otherwise have to guess.

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?

An output schema exists, so return values needn't be spelled out, and the description covers signal definitions, thresholds, and truncation. What remains unaddressed is behavior on empty/insufficient data (e.g. no scheduled posts in window) and whether results are scoped to one account – minor gaps for a read-only diagnostic tool.

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%, including defaults and max values for lookback_days/lookahead_days and an enum for response_format, so the schema carries parameter meaning. The description restates the response_format behavior almost verbatim from the schema and adds no syntax, default, or interaction detail for platforms or the time windows – 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 ('Returns derived signals over the account's content calendar') and then enumerates the exact derived signals with thresholds: clusters (3+ posts in 4h), gaps (>72h), stale drafts (>14d), pending proposals, cadence drift. That enumeration makes it unmistakably distinct from the plain listing sibling get_calendar without needing to name it.

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?

Usage is implied by the nature of the tool – an agent can infer it is the diagnostic/anomaly view of the calendar – but the description never states when to reach for this instead of get_calendar or get_performance_insights, nor any precondition (e.g. whether a platform must be connected first). The response_format tradeoff is the only explicit selection guidance offered.

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