avanza_account_performance

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

With no annotations provided, the description carries the behavioral burden. It explicitly says 'Read', making the non-mutating nature clear, and reveals useful stateful behavior: the account may come from a prior selection or be supplied directly. It does not disclose session/auth prerequisites, error behavior, or output shape, but the core read-only behavior is present.

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?

The description is one compact sentence that front-loads the verb and resource and contains no filler. The phrasing 'performance/development' is slightly awkward, but the structure is efficient and easy to scan.

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 tool with no annotations, no output schema, and four optional parameters, this description is thin. It does not describe what the performance output contains, what happens if neither a selected account nor an account_id is available, or whether session context is required. Given the large family of Avanza session and account tools, an agent would still need to infer several invocation details.

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 schema leaves account_id undocumented, and the description adds meaning by saying it can be 'selected or supplied', which clarifies that the parameter is optional when a selected account exists. It also confirms period is user-chosen, though it adds little beyond the schema's enum and default. Session parameters are already described in the schema, so the description only partially compensates for the low schema coverage.

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 states a clear verb ('Read') and a specific resource ('Avanza account performance/development'), and it identifies the controlling variables: account_id and period. It is clear enough to convey the tool's primary job, but it does not explicitly differentiate it from nearby account tools such as avanza_accounts or avanza_portfolio.

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 implies when the tool should be used: to retrieve account-level performance over a period. It also gives one useful practical rule: account_id can be the currently selected account or an explicitly supplied ID. However, it does not state exclusions, prerequisites, or alternatives among the many Avanza sibling tools.

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