get_meta_auction_rankings

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

No annotations, so the description carries the full burden and does well: it discloses the sort order (worst offenders to top), the below_average_count output, the default min_impressions threshold and why it exists (Meta never assigns labels under that volume), and the underlying endpoint (/act_<id>/insights at level=ad). It does not state auth requirements or rate limits.

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?

Dense but front-loaded: the return payload and label set come first, then the computation, then the sort rationale, then the filter. Every clause is informative; slightly long but not padded.

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 7-param read tool with 100% schema coverage and no output schema, the description explains the returned fields, the label semantics, the default threshold behavior, and the sort output. An agent has everything needed to call it correctly; only auth/permission context is absent.

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%, so the baseline is 3. The description reinforces the min_impressions default and its rationale and the meaning of the date range defaults (today, 30 days ago), adding minor value beyond the schema but not new syntax or constraints.

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 Meta's three auction-ranking labels per ad) and enumerates the exact labels and value domains. An agent can distinguish this from siblings like get_meta_campaign_performance or get_tiktok_auction_rankings 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?

Clearly establishes context: it filters out low-volume ads and surfaces worst offenders. It names the sibling Meta MCP tool (`ads_insights_auction_ranking_benchmarks`) for the same data, implying equivalence, but does not state when to prefer this tool over that one or over get_meta_campaign_performance.

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