Who am I

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

With readOnlyHint=true already covering the safety profile, the description adds real value beyond annotations by naming the returned fields (email, organization, plan, limits) and disclosing a failure state (not logged in). It does not describe rate limits or auth requirements, but for a no-arg read tool this is close to complete.

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?

Three short sentences, zero filler, with the purpose and the "call this first" directive front-loaded before the fallback path. Every clause earns its place.

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 no-parameter read-only tool whose annotations already declare its safety profile, the description covers purpose, invocation ordering, returned content, and the error path. With no output schema, the enumerated return fields are exactly the right compensation.

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 per the baseline there is nothing for the description to disambiguate; the schema is trivially complete. No parameter-level guidance is needed or missing.

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 resource and scope: the current buildtree login and account, enumerating what is reported (email, organization, plan, limits). It distinguishes itself from buildtree_login by routing on the not-logged-in case, though it never clarifies how it differs from the sibling buildtree_login_status, which an agent could easily confuse it with.

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?

It gives explicit sequencing ("Call this first") and a concrete conditional alternative ("If it reports not logged in, use buildtree_login"). The agent knows both when to call this tool and where to go on failure, leaving nothing to inference.

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