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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered elsewhere. The description adds the useful detail that the payload includes connection status as well as metadata, but says nothing about auth requirements, what happens for a disconnected or unknown account, or error behavior. With annotations carrying the safety burden, a 3 is appropriate.

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?

A single front-loaded sentence with no filler or redundancy. Every word contributes: the verb, the cardinality, the resource, and the two things returned.

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 simple two-parameter read tool with full schema coverage and no output schema, the description conveys what is fetched and implicitly what comes back (metadata plus connection status). It is nearly complete; only edge-case behavior (missing/disconnected account) is unaddressed, which is a minor gap given the annotations.

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%: accountId already says 'An accountId from list_accounts' and profileId documents its default binding, so the schema does the heavy lifting including the cross-tool provenance hint. The description adds no parameter detail beyond that, so the baseline 3 is correct.

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 gives a specific verb ('Return') and a precise resource ('one connected account's metadata and connection status'), which cleanly separates it from the plural list_accounts. It does not, however, name or differentiate itself from near-neighbors like ads_get_account or refresh_accounts, so it falls short of a 5.

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 only implied: 'one connected account' signals a single-record lookup rather than a list, which is enough to distinguish it from list_accounts in practice. There is no explicit when-to-use statement, no prerequisites, and no named alternative for cases where the agent might want bulk data.

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