accounts_use

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

With no annotations, the description carries full burden. It explains input format ('full UUID or a unique prefix'), output ('resolved account name and id, or an error'), and intended effect ('set active billing account'). It does not explicitly state side effects or idempotency, but given the simple nature, it is nearly 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 sentences, front-loaded with purpose, then usage guidance, then input/output specifics. No redundant words; every sentence serves a distinct role. Excellent conciseness for a single-parameter tool.

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?

Given the tool's simplicity (one param, no output schema, no nested objects), the description covers all necessary context: what it does, when to use it, how to provide input, what to expect as output. No gaps remain.

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 coverage is 100%, so baseline is 3. The description essentially repeats the schema's parameter description. No additional meaning is added beyond what the schema already provides, though the usage context is helpful.

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 clearly states the action: 'Set the active billing account that project commands operate on.' It specifies the verb 'Set' and the resource 'active billing account'. It distinguishes from siblings like accounts_list (list accounts) and accounts_create (create accounts), making its unique purpose obvious.

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?

Explicitly states when to use: 'after login when you belong to more than one account, before using projects_list, projects_create, or projects_use.' It also directs to accounts_list for valid IDs. Provides both procedural context and prerequisite knowledge, leaving no ambiguity.

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