get_portfolio_summary

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuine behavioral context by noting results are merged/aggregated across all accounts, but says nothing about latency, cost, freshness of P/L, or data scope limits.

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?

A single sentence, front-loaded with the scope phrase and then a compact enumeration of contents. No filler, no redundancy with annotations or schema.

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?

An output schema exists, so return structure need not be explained, yet the description helpfully enumerates the key fields. For a zero-required-parameter read tool with full annotations and full param coverage, this is nearly complete; only explicit routing guidance against siblings is missing.

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 description coverage is 100% and top_n is fully documented in the schema with a default of 10 and bounds 1-50. The description's 'top holdings' hints at top_n but adds no meaning beyond the schema, so the baseline 3 is correct.

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?

Specific verb+resource ('get_portfolio_summary') with a full enumeration of the contents: total value, cash, today's P/L, unrealized P/L, allocation, top holdings, per-account totals. The phrase 'one-shot overview across all accounts' and 'merged across accounts' clearly distinguishes it from granular siblings like get_positions or list_accounts.

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 implied usage ('one-shot overview') tells the agent this is the aggregate call rather than a granular one, which is useful context. However, it never explicitly states when to prefer it over get_positions/list_accounts, nor any exclusions or prerequisites. Usage is inferable but not stated.

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