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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds real value beyond them: the returned fields, the visibility limitation ('only workspaces your account can open'), and the auth requirement ('Cotlet API key with access to this app').

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?

Four short sentences, front-loaded with what the tool returns and the role breakdown. Each sentence contributes (scope, fields, usage, auth), though the role enumeration and auth note could be marginally tighter.

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?

With no output schema and no parameters, the description carries the full explanatory burden and largely meets it by naming the returned fields and access scope. It is complete enough to invoke correctly, lacking only an explicit note on pagination or ordering for a list result.

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 the baseline is 4. The description correctly supplies no input syntax and instead explains how the output values are consumed elsewhere, which is appropriate for a no-arg tool.

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?

States a specific verb and resource ('workspaces your Expensify account belongs to') plus the exact fields returned and the caller's role. The scoping phrase 'only workspaces your account can open' distinguishes it from the single-workspace sibling expensify_get_workspace.

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?

Gives clear downstream context: 'Use the name or ID as the workspace parameter in the other tools,' establishing this as the entry point for obtaining workspace identifiers. It does not, however, explicitly contrast itself with expensify_get_workspace or state a when-not condition, so it stops short of a 5.

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