companies_select

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

With no annotations provided, the description carries full burden and does disclose the key behavioral trait: that this sets the X-Company header that will affect all subsequent company-scoped requests. It also notes the session-scoped nature of the selection. It doesn't mention persistence/across-session behavior, but the session-scoping is clearly disclosed.

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, each earning its place: what it does, how it works (X-Company header), and prerequisite. Zero wasted words.

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 single-parameter, side-effect-note tool, the description fully covers the mechanism (header setting), the prerequisite (companies_list), and the scope (session-wide effect on subsequent requests). No output schema needed for a side-effect operation. This is complete.

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% and the single parameter (companyId) is well-described in the schema. The description reinforces that the companyId is a UUID and explains its session impact, but doesn't add substantially beyond the schema since the schema itself already explains this is the active company context.

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 verb (select), resource (active company for session), and the mechanism (sets X-Company header). It distinguishes from sibling companies_create/update/delete by focusing specifically on session active-company selection.

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 description explicitly instructs to call companies_list first to find available company UUIDs, which is useful prerequisite guidance. However, it doesn't mention when selecting is necessary vs. when the default company context applies, or that this is a session-scoped action.

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