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

No annotations are provided, so the description carries the full behavioral burden — and it handles this well. It discloses that data is fetched 'live from Meta' (not cached), explains the match_rate_approx sentinel value (-1 = not enough data yet), and enumerates returned fields. For a read-only audit tool, the disclosed behaviors are sufficient, though it doesn't cover error conditions or pagination.

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?

The description is information-dense with no filler; it front-loads the core purpose and field list before moving to usage and sibling differentiation. It is longer than average but every clause earns its place given the absence of an output schema that would otherwise document return fields.

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 no output schema, the description compensates by enumerating the returned configuration fields and their semantics inline. It covers the primary use cases, sourcing of required inputs, and sibling relationships. Minor gaps (e.g., what 'data-use setting' values look like, error behavior) are acceptable for this read-audit 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 description coverage is 100%, so both parameters (pixel_id and ad_account_id) are already well-documented in the schema. The description references getting pixel_id from a sibling tool but adds no parameter-specific meaning beyond the schema. Baseline 3 is appropriate since the schema does the heavy lifting.

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 ('Get a Meta pixel's configuration details') and enumerates the exact fields returned (automatic advanced matching, matched customer-info fields, match_rate_approx, first-party cookie status, data-use setting, last fired time, owning business). It also explicitly distinguishes itself from sibling tools by naming adsap_get_pixel_stats and adsap_get_pixel_health as complements, so an agent can clearly tell it apart.

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?

States explicit when-to-use scenarios: 'Use to audit pixel setup / event match quality before optimizing campaigns, or to check a pixel is alive (last_fired_time).' It also instructs where to source the pixel_id (from adsap_list_meta_assets) and names complementary siblings. It lacks explicit when-not-to-use exclusions, but the guidance is clear and actionable.

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