meta health check

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds genuinely valuable context beyond annotations: the tool 'warns about missing read scopes' (a diagnostic behavior) and critically guarantees it does so 'without exposing the access token' — a security property no annotation covers. No contradiction with the readOnlyHint annotation; the description's 'read-only' aligns with it.

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?

One sentence of 23 words, front-loaded with the core identity ('Agent-ready read-only health check') followed by a compact enumeration of the three behaviors. The closing safety clause ('without exposing the access token') earns its place as a high-value behavioral guarantee. Zero filler words; every clause adds information.

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 zero-parameter, read-only tool with a full annotation safety profile and an output schema that presumably documents return values, the description covers everything an agent needs to call it correctly: what it validates, what it lists, what it warns about, and the token-exposure guarantee. The only gap is the absence of sibling differentiation, which is more of a usage-guideline concern, and no mention of error behavior on an invalid token — minor given the output schema.

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?

The tool has zero parameters and schema coverage is trivially 100%, so the baseline of 4 applies. There is nothing for the description to document or explain about inputs, and it correctly does not invent parameter guidance. The description's focus on behavior rather than inputs is appropriate for a no-arg health check.

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 names a specific composite action ('health check') with three concrete behaviors: validates token metadata, lists accessible ad accounts, warns about missing read scopes. This is far more specific than the title alone and effectively distinguishes the tool from single-purpose siblings like meta_debug_token or meta_list_ad_accounts. It stops short of a 5 only because it never explicitly names a sibling or contrast to preempt confusion.

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 rather than stated: 'Agent-ready' and the health-check framing suggest this is a preflight diagnostic an agent runs before performing operations, but no explicit when-to-use, when-not-to-use, or alternative routing is given. Given 40+ sibling tools, including the overlapping meta_debug_token, an explicit 'use this first, use meta_debug_token for deep token inspection' sentence would have moved this to a 4.

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