Robin Saige we check the tools AI agents call

send16 mcp

io.github.spruikco/send16-mcp

Email for AI agents: send mail, manage contacts, automations & webhooks. Zero-DNS first send.

— the operator's own registry description reported

Publisher io.github.spruikco · first seen 2026-08-12 · endpoint https://mcp.send16.com/mcp

allow
verdict
rich-slow-solo
cluster
ok_tools
answers
79
tools served

Dependency rating derived

allow
allow — alive & usable · action ● · V n/a
allow — because answers ●, 79 tools legible (band A) ●, no confirmed drift in 2 probes ●; not yet checked: truth (0 runs)

Cluster rich-slow-solo · distinctiveness 0.505 (moderate). Every figure is a percentile or class within the 11,094-server censussee the whole spectrum.

Does it answer? Q1 · observed
answersalive_tools
latency373 ms
vs populationslow
protocolcurrent
authopen
Can it be used? Q4 · observed
tools79
vs populationhigh
capabilities1
harnessA
Did it hold when checked? Q3–Q4 · derived
identitysolo
servers on its host1
verifiabilityunassessed
duplicate inventoryno
drift events0
answers trueno primary

🔏 Signed receipt rr_2b24e9b3220aa8e1f0c5ed12 · ed25519 · key rs-rcpt-2026-08 — this rating is tamper-evident; an agent gets the full signature from check_server and can verify it against the published key.

Q1Does it answer?alive & usable — 2 probes ●evidence ↓
Q2What is it?action ● evidence ↓
Q3Can it be checked?V n/a for this kind ◐evidence ↓
Q4Did it hold?harness A · truth not yet run · no drift ●evidence ↓
Q5What company does it keep?rich-slow-solo · 1 on its host (context, not verdict) ◐evidence ↓

● observed · ◐ derived · ○ reported — the verdict synthesizes Q1–Q4; Q5 is context. Methodology →

History observed

Every probe we made, oldest → newest (2 shown, 2026-08-12 → 2026-08-14). Green answered · amber answered-but-walled · red no useful answer. A gap in our cadence is a gap in coverage, not evidence about the server.

changelog (1 events)
datetypewhat changed
2026-08-12outcomefirst probe: ok_tools

What kind of tools these are derived

Verification only means something relative to a tool's NATURE — an email-sender has no "true answer", a generator has no answer key. Classification evidence: classified from tool names/descriptions/annotations WE OBSERVED. What checking applies to each kind (the full methodology →):

naturetoolsmeaning what checking applies
action46changes the worldno true answer exists; we check the CONTRACT (destructive/read-only/idempotent declarations, error legibility) and never fire real actions
retrieval-public21serves public factstruth-checkable against a public source — the V-ladder applies in full
unclassified6not classifiable from its textTier-1 only until its tools describe themselves
generative5creates contentno answer key exists; disclosure + stability checks, never truth verdicts
retrieval-private1serves the caller's own dataoutside truth-checking is impossible BY NATURE, not by failure — the operator-invited pathway applies

Tools last seen observed

activate_automation add_contacts_to_audience add_convo_note add_domain add_suppression check_domain_health create_action create_audience create_campaign create_contact create_topic create_webhook delete_action delete_audience delete_campaign delete_contact delete_topic delete_webhook design_email_template duplicate_campaign enroll_in_automation generate_email_from_url get_action get_automation get_automation_stats get_brand get_campaign_stats get_contact_health_score get_contact_timeline get_convo get_deliverability_status get_message get_message_events get_template get_workspace get_workspace_usage import_contacts list_actions list_audiences list_automation_enrollments list_automations list_campaigns list_contacts list_convos list_domains list_inbox_counts list_messages list_segments list_suppressions list_templates list_topics list_webhooks list_workspaces mark_convo_read pause_automation pause_campaign pre_send_review preview_campaign_recipients preview_segment regenerate_webhook_secret remove_contact_from_audience remove_suppression render_email_content resume_campaign schedule_campaign screener_decide search_contacts send_broadcast send_campaign_test send_email send_event send_reply update_action update_brand update_campaign update_contact update_convo update_topic whoami

Harness readiness observed

Can an agent's harness pick this tool and call it correctly? Graded on the three things an agent reads — name, description, typed parameters. Band A — an agent can pick and call these reliably.

legibility checktools passingok
name is clear & specific79/79
has a description79/79
description is substantive73/7973/79
parameters are typed79/79
parameters are described66/7966/79

79 of 79 tools graded · 79 with a captured input schema. RS-008, Tier-1 — no domain knowledge, applies to any tool. “Alive” is not the same as “usable”.

Truth checks observed

Not in the Tier-2 trade lane, or not yet checked. Tier-2 re-derives a server's answers against published primary sources — see truth checks.

Protocol conformance observed

2025-06-18
protocol version
session model
0.5.13
server version send16

Capabilities: tools

Drift observed

No confirmed drift on record. Baseline set 2026-08-14; changes appear here after human review.

raw probe records
probed (UTC) outcomehttpmsprotocol
2026-08-14T20:00:13Zok_tools2003732025-06-18
2026-08-12T05:35:25Zok_tools2003612025-06-18

Watch or embed this verdict

verdict badge

Operators: put the live verdict in your README — it updates with every census, links back here, and is a dated observation, never a warranty:

[![Robin Saige verdict](https://robinsaige.com/badge/io.github.spruikco/send16-mcp.svg)](https://robinsaige.com/s/io.github.spruikco/send16-mcp)

Depend on it? Subscribe to its change feed — outcome changes and confirmed drift, no account needed. Building on it? The full dossier as JSON — verdict, rating, truth checks, history — stable enough to gate CI on.

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