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

Annotations already declare non-readOnly, idempotent, non-destructive, closed-world. The description adds two useful behavioral facts: ownership is required and CAS is available. It does not disclose whether omitted fields are left untouched (partial update) or cleared, which is the key behavioral question for a 10-optional-field mutation.

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 tight sentence with the resource and the concurrency option front-loaded and no filler. It is arguably too terse for an 11-parameter mutation, but nothing written is wasted.

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?

With 11 parameters, 18% schema coverage, no output schema, and no annotations explaining write semantics, the definition leaves major gaps: partial-vs-full update behavior, the meaning of status/signal_type values, and what a successful update returns.

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 only 18%, so the description must compensate for ten undocumented fields (notes, status, product, currency, deadline, location, quantity, price_cents, signal_type). It only references expected_updated_at, which the schema already fully documents, so it adds almost nothing on parameters.

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 (update) and resource (market_signal) and adds the ownership scope constraint. Siblings (market_signal_create/read/list) are distinguishable by verb alone, though none are named explicitly.

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 phrase 'you own' implies a permission precondition, and the parenthetical flags the optional concurrency path via expected_updated_at. There is no explicit when-to-use-vs-alternatives guidance (e.g., create vs update, or when CAS is required rather than optional).

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