Read 30-day completed heartbeat windows, daily counts, gaps and streaks. Owner key required unless publicly shared; self-reported receipt evidence, not uptime. Incomplete windows excluded; registration-anchored windows have no grace. Shares 60 reads/IP/minute with presence badges and signed evidence. Heartbeat mode only.
| Name | Required | Description | Default |
|---|---|---|---|
| api_key | No | ||
| agent_id | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
Input schema / properties / api_keyAdded value: +{
+ "anyOf": [
+ {
+ "type": "string"
+ },
+ {
+ "type": "null"
+ }
+ ],
+ "default": null,
+ "title": "Api Key"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the read-only annotations, it discloses a shared rate limit (60 reads/IP/minute with presence badges and signed evidence), the credential requirement, the trust caveat ('self-reported receipt evidence, not uptime'), and record-exclusion semantics. That is exactly the kind of context annotations cannot carry.
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?
Dense and front-loaded: the primary function comes first, then caveats, auth, exclusions, and rate limits. A stray mid-sentence line break and telegraphic phrasing slightly hurt readability but no sentence is filler.
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 shape need not be explained, and the description covers data meaning, trust caveats, auth, exclusions, and rate limits. The only real gap is not directing the agent to a sibling when the requested mode or evidence type does not match this tool.
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 0% for 2 parameters. The description explains the owner-key condition, which covers api_key semantics, but adds nothing about agent_id beyond what its name implies. Baseline 3 is right since one parameter is effectively undocumented.
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?
The description names a specific verb (Read) and a tightly bounded resource: 30-day completed heartbeat windows, daily counts, gaps and streaks. The qualifiers 'Heartbeat mode only' and 'self-reported receipt evidence, not uptime' separate it from status/assessment siblings like agent_health_status or agent_endpoint_assessment.
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?
It states an auth condition ('Owner key required unless publicly shared') and a mode exclusion ('Heartbeat mode only'), plus which records are excluded (incomplete windows, no grace for registration-anchored windows). It stops short of naming which sibling to use instead for other presence or evidence needs, so it is clear context without explicit alternative routing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.