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

The annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered; "Changes nothing" largely restates that. The one piece of added value is framing the result as a property of the connection rather than the account, which helps the agent interpret it correctly.

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 short sentences, front-loaded with the purpose, with no filler. The trailing "Changes nothing" slightly duplicates the read-only annotations rather than earning its place, which keeps it just below top marks.

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 and the tool is parameterless, so the description needn't explain return values or inputs; what it does say is sufficient to invoke the tool correctly. The only missing piece is a pointer telling the agent why it would pick this over the closely named get_account sibling.

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 takes zero parameters, so there is nothing for the description to disambiguate; baseline is 4. No parameter guidance is needed or expected here.

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?

"Reads which account this connection is signed in as" names a specific verb and a well-defined resource, making it clear this returns identity for the current connection rather than account data. It does not, however, explicitly distinguish itself from the very similar sibling getmattered_get_account or getmattered_get_application_profile, leaving the agent to infer the difference.

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?

The clause "which tells connected accounts apart" implies the use case (disambiguating multiple connections/credentials), which is genuinely helpful context. But there is no explicit when-to-use versus get_account, no stated prerequisites, and no exclusions.

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