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

With no annotations provided, the description carries the full burden and meets it: it leads with '⚠ MUTATING,' discloses that mode 'replace' removes old strategies while 'append' keeps them, states the prerequisite to 'subscribe first' for monetized portfolios, and reveals the return shape. These side effects and preconditions appear nowhere in structured annotations, making this genuinely additive.

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 compact and dense but every sentence earns its place: mutation warning and purpose are front-loaded, followed by target/mode semantics, the monetization prerequisite, the return shape, and routing guidance. No filler or repetition of schema content.

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 5-parameter mutating tool with no annotations and no output schema, this description is remarkably complete: safety profile, mode semantics, the subscription prerequisite, the return value shape (forkSharedPortfolioResult fields), and usage routing are all covered. The one conditional dependency (target_portfolio_id required when target=existing) is left to the schema, which is acceptable given 100% schema coverage.

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%, so the baseline is 3; the description adds meaning by disclosing that mode defaults to 'replace' — a fact absent from the schema, which has no default field — and spelling out the behavioral consequence of each mode choice. The remaining parameters are fully documented in the schema, so the description does not need to repeat them.

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 — 'fork strategies from a shared portfolio into the user's account' — and clarifies the two target behaviors ('new' creates a chat portfolio, 'existing' patches a deployed portfolio). The closing line 'Prefer fork when the user wants to edit/customize strategies' differentiates it from siblings such as backtest_portfolio, clone_strategies_to_portfolio, and fetch_portfolios.

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 gives explicit when-to-use guidance: 'Prefer fork when the user wants to edit/customize strategies.' However, it does not name alternative tools or state when not to use it; the copy_trade_shared alternative for continuous mirroring appears only in the schema's shared_portfolio_id description, not in the tool description itself.

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