market_depth

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

The description adds real behavior beyond the annotations: it will not open UI panels on the agent's behalf and it fails closed rather than inferring bid/ask sides from row position. But it doesn't say what actually happens on an ambiguous panel (error vs. partial return) or how target_id/symbol mismatches behave, which the annotations (readOnly, non-idempotent, openWorld) don't cover.

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?

Two tight sentences with the scope and precondition front-loaded; nothing is wasted. The second sentence is slightly cryptic because 'requires explicit bid/ask row labels' reads like a parameter requirement when no such parameter exists.

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 read tool with four guard parameters and no output schema, the description never indicates what comes back (bid/ask levels up to limit?), nor clarifies that the expected_* parameters are mismatch guards. Adequate to recognize the intent, insufficient to invoke confidently.

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 75%, so the baseline is 3. The description mentions no parameter at all — nothing about limit (row count), target_id tab selection, or expected_symbol/expected_layout_id guard behavior — so it adds nothing over the schema.

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: 'Read an already visible depth panel'. The qualifier 'already visible' and 'without opening trading controls' scopes it away from navigation/trading siblings, but no sibling tool (e.g. quote_get, data_get_ohlcv) is named for contrast.

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?

Implies when-to-use (an on-screen depth panel already exists) and a when-not ('without opening trading controls'), plus a precondition about explicit bid/ask labels. However, it never names an alternative tool or says what to do when no depth panel is visible, leaving the routing decision to inference.

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