zabbix_api_call

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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint, so the safety profile is covered; the description still adds real value by disclosing the risk-registry refusal for unknown methods, the approval flow for writes, and the MCP read-only surface. Minor ambiguity remains between 'write methods produce a plan' and 'a write through this tool is refused', and it never says what the raw response looks like or whether it is paginated.

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?

Front-loaded and logically ordered: what it does, how reads vs writes behave, then routing. Slight redundancy — the write refusal is stated twice ('go through approval', 'Over MCP this tool is read-only', 'A write through this tool is refused') — but each restatement disambiguates a genuinely confusing surface.

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 no output schema, the description should ideally describe the return shape (raw Zabbix JSON), which it omits. It is otherwise complete for the routing decision an agent must make, covering read immediacy, write refusal, unknown-method refusal, and sibling alternatives.

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% with only 2 params, so the schema already documents 'method' and 'params as JSON'. The description contributes only an inline example (host.get) and no format, pagination, or limits guidance beyond the schema — baseline 3 applies.

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 ('Call a Zabbix API method directly') and positions itself precisely as the raw escape hatch against a list of high-level siblings. An agent can distinguish it from zabbix_problems, zabbix_metrics_latest, etc. without opening either schema.

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?

Explicit routing: 'Use when no high-level tool covers the question and a read method such as host.get is required', with a named fallback for problems/hosts/metrics/alert delivery and a redirect to zabbix_write or zabbix_plan_create for writes. When-to-use, when-not-to-use, and alternatives are all stated.

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